>>WELCOME.
THANK YOU ALL FOR BEING HERE AND
SPECIAL THANKS TO OUR SPEAKER
DR. JUDITH FRYDMAN.
IT IS MY PLEASURE TO WELCOME YOU
AND INTRODUCE THIS WALS LECTURE
TODAY.
NOW SOME INFORMATION ABOUT OUR
SPEAKER.
SHE IS THE DONALD KENNEDY CHAIR
IN THE SCHOOL OF HUMANITIES AND
SCIENCES AND PROFESSOR OF
GENETICS AT STANFORD UNIVERSITY.
AND YOU CAN TELL WHEN HUMANITIES
AND SCIENCES ARE JUXTAPOSED THAT
WE'RE IN FOR A VERY SPECIAL
TREAT TODAY.
THERE IS NO QUESTION.
A LONG-STANDING INTEREST IN
PROTEIN FOLDING AND IN PROTEIN
MISS FOLDING.
HOW IS IT THAT A PROTEIN AS IT
TRAVERSES THROUGH ITS LIFETIME
AS IT GETS PICKED UP AS BEING
READY FOR DISPOSAL HOW IS IT
THAT IT KNOWS HOW TO FOLD?
WHAT HAPPENS WHEN IT MISS FOLDS
BOTH IN THE CELL AT THE
MICROSCOPIC LEVEL AND ALSO TO
INDUCE DISEASE IN ALMOST ANY
ORGAN SYSTEM IN THE BODY.
7 OUR LABORATORY HAS UNCOVERED
BASIC PRINCIPLES OF CHAPERONE
ACTION IN DENOVO PROTEIN FOLDING
AND RECENT WORK FROM HER LAB
SUGGEST THAT PROTEIN MISS
FOLDING PLAYS A ROLE IN NEURO
DEGENERATIVE DISEASES AND IN
AGING THROUGHOUT THE BODY.
THIS REALLY SUGGEST THE
POTENTIAL FOR THERAPEUTIC
STRATEGIES AIMED AT CHAPERONES
AND AT THESE MISS FOLDED
PROTEINS.
DR. FRYDMAN RECEIVED BOTH FROM
THE UNIVERSITY OF BUENOS AIRES.
AND THEN DID A SECOND FELLOWSHIP
AT SHOWN KEPT ERRING INSTITUTE.
SHE MOVED TO STANFORD IN 1996.
AND LITERALLY CLIMBED THE
ACADEMIC LADDER AND BECAME A
FULL PROFESSOR WITH TENURE IN
2010.
SHE HAS EARNED MANY, MANY, MANY
AWARDS AND ACCOLADES INCLUDING
IN 2021 BEING ELECTED TO THE
NATIONAL ACADEMY OF THE
SCIENCES.
SHE IS TRULY PASSIONATE ABOUT
MENTORSHIP.
AND HAS HAD MANY, MANY TRAINEES
IN HER LABORATORY MANY OF WHOM
HAVE BEEN FROM GROUPS THAT ARE
UNDER REPRESENTED IN SCIENCE AND
MEDICINE AND THE PRODUCTIVITY
NOT ONLY OF HER OWN LAB BUT OF
THE LABS THAT HER MENTEES HAVE
ESTABLISHED IS REALLY LEGENDARY.
AND I WOULD LIKE TO GIVE A SHOUT
OUT TO THE COCHAIRS OF THE
PROTECT OHIO STATION US -- GROUP
WHO NOMINATED TODAY'S * SPEAKER
AND ARE RESPONSIBLE FOR HER
COMING TO VISIT US TODAY.
SO WITHOUT FURTHER ADO HER TALK
IS TITLED MOLECULAR ORIGAMI,,THE
DELICATE ART OF PROTEIN FOLDING
AND MISS FOLDING AND ITS
RELEVANCE TO HEALTH AND DISEASE.
WELCOME AND WE'RE LOOKING
FORWARD TO YOUR TALK.
[ APPLAUSE ]
>> THANK YOU SO MUCH FOR THAT
VERY GENEROUS INTRODUCTION.
FREEDMAN.
>>THANK YOU FOR THE INVITATION.
I'M HAVING A WONDERFUL DAY.
REALLY LEARNING A LOT.
IT'S WONDERFUL TO SEE SO MANY
OLD FRIENDS AND COLLEAGUES AND
I'M REALLY HAVING A GREAT TIME.
SO WHAT I HOPE TO DO TODAY IS
GIVE YOU AN OVERVIEW OF THE KIND
OF PROBLEMS AND THE KIND OF WORK
WE DO IN THE LAB TRYING TO
UNDERSTAND HOW PROTEINS FOLD IN
THE CELL AND HOW THE CELL
MANAGES THEIR PROTEIN.
I DON'T KNOW IF YOU SEE MY
CURSOR.
MAYBE I CAN SO WHEN I STARTED TO
BECOME INTERESTED IN HOW
PROTEINS FOLD IN THE CELL OUR
THINKING WAS STRONGLY INFLUENCED
BY THE THINKING OF THE FIELD BY
-- EARLY EXPERIMENTS THAT SHOW
THAT THE INFORMATION FOR THE
UNIQUE THREE DIMENSIONAL
STRUCTURE OF PROTEINS IS SOMEHOW
ENCODED IN IT'S MEAN OH ACID
SEQUENCE.
THE THINK WAS * INPUT WAS NOT
GETTING PROTEINS MADE AND ONCE
THEY WERE MADE IN RIBOSOMES --
-- I WILL SHOW YOU TODAY
PROBABLY THIS IS PERHAPS THE NOT
TOTALLY GENERALLY APPLICABLE AND
THERE MIGHT BE SOME PROTEINS
THAT ESCAPE THIS GENERALIZATION
BUT EVEN FOR THOSE THAT DO HAVE
-- YOU CAN THINK OF THESE A
LITTLE BIT AS THE JAPANESE ART
OF ORIGAMI WHERE HAVE A SET OF
DETAILED INSTRUCTIONS FOR UNIQUE
THREE DIMENSIONAL SHAPE BUT WHEN
YOU TRY TO DO THEM YOU END UP
WITH A PRODUCT THAT HAS TO BE
SUBJECT TO QUALITY CONTROL AND
WHEN YOU THINK HOW THIS PROCESS
HAPPENS IN THE CELL IT'S NOT
JUST ONE PROTEIN FOLDING BUT
IT'S A HUGE AND VERY DENSE AREA
OF BOTH FOLDED AND FOLDING
PROTEINS SO THE POTENTIAL FOR
PROBLEM MAY BE ACTUALLY VERY
HIGH.
SO KIND OF A WAY TO ENVISION
THIS PROBLEM I OFTEN THINK AND
USE AS AN ILLUSTRATION THIS
STRUCTURE WHICH IS THE STRUCTURE
OF THE COMPLEX SWAN --
ILLUSTRATES THE COMPLEXITY OF
FOLDING.
THIS IS A NATIVE COMPLEX THAT
HAS TRANSLATED TO MITOCHONDRIAL.
SOME TRANSVERSE MEMBRANES.
OTHERS FOLD INTO THE SOLUBLE
PHASE.
ALL NEED TO MEET AND ASSEMBLE
CORRECTLY AND BEGIN THEIR
CORRECT CO-FACTORS.
WHEN YOU ABOUT ABOUT HOW THESE
ASSEMBLE IT'S MORE DIFFICULT.
BY THE SAME TOKEN YOU CAN ASK
WHAT HAPPENS IF ONE OF THOSE --
ARE DESTABILIZED.
DOES THIS SUB UNIT GET REMOVED
AND REPLACED WITH A NEW ONE?
DOES THE WHOLE COMPLEX GET
DEGRADED?
HOW ARE THE DECISIONS TO AFFECT
THE QUALITY OF THE PROTEIN
IMPLEMENTED.
THESE ARE THE TYPES OF QUESTIONS
THAT I'M INTERESTED IN MY LAB
AND I THINK THE FIELD IN GENERAL
IS INTERESTED IN.
SO WE WANT TO UNDERSTAND HOW
THEY WORK AND OF COURSE THERE IS
ANOTHER LEVEL OF COMPLEXITY
WHICH IS THAT ALL OF THESE HAS
TO HAPPEN IN THE COMPLEX
ENVIRONMENT OF THE CELL.
SO PERHAPS BECAUSE OF THE
COMPLEXITY OF THE PROBLEM OVER
THE LAST 20 YEARS IT HAS BECOME
APPARENT THAT DEFECTS IN PROTEIN
FOLDING AND QUALITY CONTROL THE
NETWORK OF PROCESSES THAT WE NOW
CALL -- ARE LINKED TO A WIDE
RANGE OF HUMAN DISEASES.
PERHAPS THE MOST FAMOUS ARE THE
AMYLOID DEPOSITS -- CAUSED BY A
CUMULATION OF UNFOLDED SPECIES.
IT'S UNCLEAR ABOUT THE
RELATIONSHIP.
MANY OF THESE DISEASES ARE NEURO
DEGENERATIVE DISEASES BUT THERE
ARE OTHERS THAT ARE LINKED SUCH.
-- LINKED.
8 THERE ARE ALSO PROTEIN FOLDING
DEFECTS THAT ARISE FROM
MUTATIONS AND GENERALLY THESE
LEAD NOT TO ACCUMULATION OF MISS
FOLDED PROTEIN BUT TO A LOSS OF
FUNCTION.
PERHAPS THE BEST STUDY IS THE
MUTATION THAT LEADS TO CYSTIC
FIBROSIS BUT THERE ARE MANY
OTHER MUTATIONS LINKED TO CANCER
ETC.
AND OF COURSE BECAUSE THE NATURE
OF PROTEINS'S ABILITIES SO
DELICATE AND AS THEY SAY
MARGINALLY STABLE A NUMBER OF
STRESSES -- CAUSE THIS HAVE BEEN
LINKED TO A NUMBER OF
PATHOLOGICAL STATES INCLUDING
STROKES.
7 AND I INCLUDE HERE -- THIS IS
NOT A DISEASE BUT PERHAPS A
DISEASE WE ALL WANT TO HAVE BUT
IT IS LINKED TO A LARGE NUMBER
OF HUMAN PATHOLOGIES AND THERE
IS INCREASING EVIDENCE THAT THE
CAPACITY OF CELLS THAT MAINTAIN
PROTECT OHIO STATION US * AND
THIS IS ONE OF THE REASONS OR
THE FACTORS THAT ARE LINKED TO
GREAT INCIDENCES OF DISEASES
THAT OCCUR WITH AGING.
IN A VERY, VERY SIMPLISTIC
MANNER WE CAN THINK OF PRO OHIO
STATION US AS THE MULTIPLE FATES
THAT HAPPEN TO A PROTEIN IN THE
CELL.
*.
WE KNOW THAT MANY CHAP REASONS
FACILITATE THIS PROCESS.
IT HAS TO BE MONITORED FOR
INTAKE TREE AND ALSO INVOLVED IN
THE PROCESS.
ALSO INVOLVED IN RESCUING OR
STABILIZING AND ONCE A PROTEIN
IS IN THE CELL BUT IS NON-NATIVE
A DECISION HAS TO BE TAKEN
WHETHER TO REFOLD IT OR SEND IT
FOR CLEARANCE THROUGH A NUMBER
OF DEGRADATION PATHWAYS.
SO THE PROTEIN IS STARTED AND
DEGRADED AND IF IT FAILS YOU
START TO ACCUMULATE MISS FOLDED
SPECIES INCLUDING AMYLOID
AGGREGATES AND WE DON'T
UNDERSTAND HOW THIS DIFFERENT
PHASE OF THE PROTEINS ARE
COORDINATED.
BECAUSE PROTEINS ARE COMPLEX AND
THE CELLULAR FATES ARE VERY
COMPLEX THE NETWORK THAT DEALS
WITH THESE PROBLEMS IS ALSO VERY
COMPLEX.
I TOOK THIS PICTURE OUT OF A
CATALOG AND WHAT I WANT TO BRING
HOME WITH THIS PICTURE IS THE
MULTIPLICITY OF DIFFERENT
STRUCTURAL AND MECHANISTIC
DIVERSITY THERE IS IN THIS
MACHINERY.
THE MACHINERY THERE ARE MANY
PEOPLE THAT WORK ON THESE --
THAT FUNCTION WITH THE UNIVERSE
OF DIFFERENT CO-FACTORS THAT
REGULATE SUB STRAIGHT BINDING
AND ACTIVITY.
THERE ARE OTHER TYPES OF VERY
LARGE MACHINES SUCH AS THE
CHAPERONES THAT ARE ALSO
DEPENDENT.
-- AND OTHER CO-FACTORS.
7 WE DON'T UNDERSTAND HOW THIS
MINNESOTA MACHINERY WORKS
TOGETHER.
ONE THING ALL CHAPERONES HAVE IN
COMMON IS THEY RECOGNIZE NO
NATIVE PROTEINS BUT BECAUSE OF
THEIR DIFFERENT STRUCTURE AND
MECHANISM EACH TYPE WILL DO
SOMETHING DIFFERENT TO THE
NATIVE PROTEIN.
SO A LITTLE TAKE HOME MESSAGE OF
WHAT I'VE TOLD YOU SO FAR IS THE
NETWORK IS VERY COMPLEX AND THIS
FUNCTION IS LINKED TO A WIDE
RANGE OF DISEASES.
I'M GOING TO GIVE YOU AN
OVERVIEW OF WORK IN MY LAB
TRYING TO UNDERSTAND DIFFERENT
ASPECTS OF THE MACHINERY.
MY FIRST INTEREST AND WHEN I
STARTED TO WORK ON THIS PROBLEM
IS WHAT HAPPENS WHEN A PROTEIN
IS TRANSLATED?
SO AT THAT TIME MOST OF THE
PARADIGMS OF FOLDING WERE KIND
OF A NUANCE IN STYLE OF
EXPERIMENT MEANING A PROTEIN WAS
FULLY MADE PROTEIN WAS DENATURED
AND THEN REFOLDED IN THE
PRESENCE OF CHAP REASON.
BUT I WAS INTERESTED IN HOW THE
CONSTRAINTS OF TRANSLATION --
PRESENTATION OF THE PEPTIDE TO
THE CYTOPLASM AFFECTED FOLDING.
THIS ESTABLISHED TWO PRINCIPLES
THAT WE'RE STILL TRYING TO
UNDERSTAND.
THE FIRST ONE IS THAT PROTEINS
START TO FOLD AND EVOLVE TO FOLD
IN A DOMAIN WEISMANER AND
SECONDLY CHAPERONES WERE
RECRUITED TO THE NASAN.
AND WHAT WE FOUND IS THAT
CHAPERONES SEEM TO BE RECRUITED
IN A SPECIFIC MANNER SUGGESTING
THERE MUST HAVE BEEN -- CROSS
TALK.
OVER THE YEARS WE'VE LEARNED A
LOT ABOUT THIS MACHINERY.
WE'VE DONE A LOT OF WORK.
TO UNDERSTAND THE PROCESSES.
ONE OF THE FIRST THINGS WAS WORK
WHERE IT WAS LOOKED AT THE
RELATION -- IN RESPONSE TO
STRESS AND THIS WORK LED HER TO
FIND THAT THERE WERE TWO
DISTINCT NETWORKS.
ONE THAT WAS TRANSCRIPTIONALLY
CO-REGULATED AND ARE INVOLVED IN
NEWLY MADE PROTEINS.
AND THE OTHER ONE WAS A NETWORK
OF CHAPERONES THAT WAS INDUCED
BY STRESS AND MANY OF THEM ARE
WELL-KNOWN PROTEINS THAT ARE
INVOLVED IN RESCUING THE
PROTEINS DURING STRESS.
OVER THE YEARS MY LAB AND MANY
OTHER LABS HAVE DEFINED A NUMBER
OF CHAP REASONS THAT INTERACT
PHYSICALLY WITH THE RIBOSOME
FACTOR.
AS WELL AS OTHER CO-FACTORS.
WHEN ONE OF THE FIRST THINGS
THAT KIND OF LIKE -- WAS
PUZZLING AT THE TIME AND YOU
KNOW WE'RE STILL TRYING TO
UNDERSTAND IS HOW DOES THE NASAN
SELECT?
SO ONE POSSIBILITIES THAT THEY
CAN ALL INTERACT AND COMPETE FOR
BINDING TO THE CHAIN BUT OVER
THE YEARS WORK FROM MY LAB
SHOWED THERE IS DISTINCT SPEAKS
I SEE -- * A SPECIFIC SUBSTANCE
OF PEPTIDES WITH SPECIFIC
DOMAINS.
THIS LEADS TO ANOTHER QUESTION.
HOW DO YOU MAKE THE RIGHT
DECISION AND WHAT DETERMINES THE
SPECIFICITY.
YOU HAVE A CHAIN EMERGING FROM
THE SITE OH PLASM.
THERE ARE * -- AND OTHER
FACTORS.
AND THEN YOU'VE MERGING FROM THE
RIBOSOME AN INCOMPLETE PROTEIN.
AND THIS HAS TO BE INTERPRETED
BY THIS SYSTEM OF EITHER
MODIFYING ENZYMES.
SO IF YOU THINK ABOUT TARGETING
AND YOU CAN SEE THIS INCOMPLETE
MOTIF -- IF YOU JUST WAIT A
COUPLE OF SECONDS THESE ACTUALLY
IS AN SRP BINDING MOTIF.
SO * THERE MIGHT BE SOME
MISTAKES MADE OR AN EQUILIBRIUM
-- HOWEVER WORK FROM PHYLLIS IN
MY LAB SHOWS THAT THERE IS
SPECIFICITY.
SO ONE OF THE THINGS THAT WE'RE
TRYING TO UNDERSTAND IS HOW DO
THESE IN -- ENSURE.
I'M GOING TO GIVE YOU A SUMMARY
AND THEN I'M HAPPY TO TELL YOU
MORE ABOUT THIS IF ANYONE IS
INTERESTED.
HOW WE'RE TRYING TO STUDY THE
PROCESS.
WE HAVE FOUND THAT BOTH HBS70
AND THE CHAPERONE -- INVITRO
THEY CAN COMPETE FOR SUB STRAITS
BUT WE KNOW THAT INVITRO THEY
INTERACT WITH DIFFERENT REGIONS
OF THE POLLY PEPTIDE.
* AND WE USE SELECTIVE RIVALS TO
IDENTIFY WHEN THIS DIFFERENT
CHAPERONS ARE RECRUITED TO THE
CHAIN AND WHEN THEY COME AFTER
THE CHAIN.
ONE EXAMPLE FROM A PAPER
PUBLISHED A COUPLE OF YEARS AGO
BY KEVIN STEIN SHOWING WHERE --
BINDS IN RELATIONSHIP TO THE
DOMAINS EMERGING FROM THE
RIBOSOME AND YOU CAN SEE THEY
HAVE DIFFERENT BINDING SITES.
THEY RECOGNIZE THAT THE DOMAINS
HAVE DIFFERENT POINTS WHEN THEY
COME OUT OF THE RIBOSOME AND
WHEN WE MAP SPECIFIC STRUCTURES
OF PROTEINS AND PROTEIN DOMAINS
WE SEE THAT IT BINDS IN SPECIFIC
REGIONS OF THE SUB DOMAINS OF
THIS PARTICULAR -- BLADE.
AND WE'RE TRYING TO UNDERSTAND
HOW THIS IS REGULATED AND HOW
THIS INFLUENCES FOLDING.
THE EXPERIMENTS THAT WE TRY TO
UNDERSTAND -- HOW IT HAPPENS
DURING TRANSLATION AND AT THE
RIBOSOME.
THERE ARE SOME PROTEINS TARGETED
BY SRP.
IT RECOGNIZES IT EARLY ON WHILE
STILL IN THE TUNNEL.
THEY BIND TO DISTINCT REGIONS
AND HAVE DISTINCT SPECIFICITY
BUT SOME ROW TEENS NEED TO HAVE
HIERARCHICAL INTERACTION.
OBVIOUSLY THE SPECIFICITY OF
CHAPERONES IS REGULATED ALSO BY
FOLDING AND WE' WE ARE INTERESTN
UNDERSTANDING.
NOW ALL OF THESE STUDIES ALSO
PROVIDED ONE SURPRISE THAT I'M
GOING TO COME BACK LATER IN THE
TALK.
WHICH IS THAT WE FOUND THAT
ELONGATION RATE.
THE RHYTHM -- IS ACTUALLY PRO
FUNDLY INFLUENTIAL TO THE FATE
OF THE POLLY PEPTIDE.
SO THE FIRST ONE TO NOTICE THIS
WAS SEBASTIAN -- THAT FOUND THAT
THERE WERE PATTERNS OF OPTIMAL
AND NONOPTIMAL -- ---AND TURNS
AND LOOPS CONNECTING DOMAINS AND
THEN THEY SHOWED THAT THE EARLY
RECOGNITION OF SRP WAS ALSO
PROMOTED BY LOCAL SLOW DOWN
REGIONS THAT FACILITATED
INTERACTION OF SRP.
8 AND FINALLY KEVIN STEIN FOUND
THAT BOTH HPS70 -- BOUND AT
REGIONS THAT ARE DETERMINED.
-- THIS TAKES THE PARADIGM
FURTHER AND THE MESSAGE AND THE
SEQUENCE ALSO CO-EVOLVED TO
ACCOMMODATE OR TO ATTUNED THE
LONG GOINGS * RATE TO PROMOTE
OPTIMAL FOLDING OR ULTIMATE FATE
OF THAT CHAIN.
THIS SUGGEST THATY LONG GOINGS
-- * I'LL COME BACK TO THIS AT E
END OF MY TALK
THE OTHER QUESTION THAT WE WANT
TO UNDERSTAND IS HOW CHAPERONES
WORK.
WHAT DO 10% OF THE PROTEINS
REQUIRE HSP70 TO FOLD?
AND ONE OF THE MAIN FOCUSES IS
TO UNDERSTAND THE MECHANISM OF
THIS RING SHAPE CHAPERONE.
AVENUE YOU CAN SEE A SIDE VIEW
OF THE STRUCTURE.
AND THIS IS THE TOP VIEW.
-- AND IF YOU TURN IT 90 DEGREES
YOU CAN SEE THAT EACH RING HAS A
CENTRAL CHAMBER THAT HAS A LEGAL
GATE.
THAT CLOSES OFF THE CENTRAL
CHAMBER AND AS I'LL SHOW YOU
THIS OPENS AND CLOSES IN
RESPONSE TO THE BINDING.
NOW AS I MENTIONED -- ABOUT 10%
-- OF THE PROTEINS IT HAS BEEN
LINKED TO A NUMBER OF DISEASE
PARADIGMS.
FOR INSTANCE OUR LAB SHOWS THAT
IT SUPPRESSES TOXICITY AND OTHER
LABS HAVE SHOWN THAT IT
SUPPRESSES AGGREGATION AND
TOXICITY.
AND TO ME THE MOST INTERESTING
ASPECT OF TRIC IS THAT THERE IS
A SUBSET OF PROTEINS THAT CAN
ONLY FOLD WITH TRIC.
THEY COMBINE TO MANY DIFFERENT
TYPES OF CHAPERONES BUT ONLY
TRIC CAN TAKE THEM TO THE NATIVE
STATE.
TRYING TO UNDERSTAND THESE
CHAPERONINS.
WE USE -- -- -- THEY ARE VERY
SIMILAR.
-- -- EACH SUB UNIT HAS THREE
DOMAINS.
ONE BINDS APT.
ONE COMMUNICATES CHANGES.
THIS IS THE LEAD SEGMENT AND
ACTUALLY THERE ARE THESE --
LITTLE TAILS THAT HAVE NOT BEEN
STRUCTURALLY RESOLVED BUT TURN
OUT TO BE QUITE IMPORTANT AND
I'LL COME BACK TO THAT.
OVER THE YEARS IN COLLABORATIONS
-- -- WE HAVE FOUND STRUCTURES
OF THE OPEN -- STATE AND OF THE
CLOSED STATE AND YOU CAN SEE
THAT THE LEAD IS OPEN IN THE
ABSENCE OF APT.
A FANCY MOVIE OF HOW ATP BINDING
AND HYDROLYSIS BINDS CLOSER OF
THE LEAD WHICH WE'RE TRYING TO
UNDERSTAND BIOCHEMICALLY.
I WANT NOW -- I TOLD YOU THE
REASON -- THEY ARE SIMILAR BUT
IT CANNOT FOLD IN THE OF THE SUB
STRAITS OF TRIC.
WHAT IS SO SPECIAL ABOUT TRIC.
OVER THE YEARS WHAT WE'VE
LEARNED IS THAT THIS -- NATURE
OF TRIC IS EXPLOITED TO GENERATE
ASYMMETRY -- SO AS TO INFLUENCE
THE FOLDING PATHWAY OF THE STUB
STRAIGHT.
SO THE * EARLIEST EXPERIMENTS
THAT LED US TO THESE -- AND WHAT
THEY SHOWED IS THAT OF THE 8 --
AS SIMILAR AS THEY ARE THERE ARE
FOUR THAT BIND ADP AND FOUR THAT
BIND ADP WITH LOWER.
WHEN THE LEAD CLOSES IT DOESN'T
CLOSE IN A CONCERTED MANNER BUT
MAY CLOSE IN A SEQUENTIAL
MANNER.
ALSO FOUND AND IDENTIFIED THE
BINDING SITE -- AND THEN SHOWED
THAT THE BINDING SITES IN THE
DIFFERENT SUB UNITS HAVE VERY
DIFFERENT PROPERTIES SUGGESTING
THAT THE TRIC CAN BIND IN A
MANNER TO DIFFERENT REGIONS.
AND FINALLY WHEN WE SOLVE THE
ARRANGEMENT OF TRIC WHICH AT THE
TIME WE DIDN'T KNOW -- AND WE
DID THIS IN COLLABORATION -- THE
BOVINE ONE AND WE FOUND THAT
INSIDE OF THE CHAMBER THERE WAS
ALSO ASYMMETRY OF CHARGES WITH
ONE HEMISPHERE BEING POSITIVELY
CHARGED AND ONE BEING NEGATIVELY
CHARGED.
SO THIS STARTED TO MAKE US THINK
THAT PERHAPS FOLDING -- VIA TR
IC WAS NOT THE SAME.
IT TUMBLES AROUND UNTIL IT FOLDS
AND WHEN THE LEAD POPS UP IT
COMES OUT BUT IN REALITY AND
THIS CAME ALSO FROM WORK WITH
NICK DOUGLAS WHEN HE WAS A
STUDENT IN THE LAB THE IDEA WAS
PERHAPS THERE WAS A SUB STRAIGHT
BINDING THAT * THAT TOGETHER
WITH THE CYCLE AND THE UNIQUE
MODE OF RELEASE WHERE ONE SUB
UNIT RELEASED FROM ITS NEIGHBOR
WILL DIRECT THE REMODELING OF
THE POLLY PEPTIDE TO THE SUB
STRAIGHT ALONG THE * SPECIFIC
FOLDING TRAJECTORY.
GUIDED TYPE OF FOLDING.
AND I'M GOING TO TELL YOU A
COUPLE OF RESULTS FROM A PAPER
THAT IS NOT YET PUBLISHED.
MAYBE IT WILL BE PUBLISHED SOME
TIME THIS CENTURY.
THAT ACTUALLY SUGGEST THAT THIS
IS THE CASE HOW TRIC PROMOTES
SUB STRAIGHT FOLDING AND THIS
WAS THE WORK OF -- POSTDOC AND
HAUN ROLE A BIOCHEMIST -- EXPERT
HAHN THAT HAS HIS OWN LAB IN
KOREA.
PURIFIED TRIC.
AND STARTED WITH ONE OF THE
CO-FACTORS.
HE RECONSTITUTED THE FOLDING
PATHWAY INVITRO AND WHAT I'M
SHOWING YOU HERE IS THAT WE
RECONSTITUTED TO LOOK AT THE
STATE OF THE SUBSTRATE DURING
THE FOLDING PATHWAY.
THE SUBSTRATE PROGRESSES FROM A
FULLY UNSTRUCTURED CONFIRMATION
TO A MORE STRUCTURED
CONFIRMATION THAT IS COMPACT BUT
NOT FOLDED WHEN BOUND TO TRIC.
TRICK.
I'M GOING TO GIVE YOU A TIDBIT
OF WHAT WE FOUND BECAUSE IT'S
VERY EXCITING.
IN THE OPEN STATE WE SEE THE
SUBSTRATE OR THE DENSITY SEEMS
TO BE INTERACTING IN THE MIDDLE
OF THE CHAMBER.
THESE ARE NEVER RESOLVED.
THE SUBSTRATE MOVES TO ONE OF
THE CHAMBERS.
WE COULDN'T REALLY RESOLVE THE
SUBSTRATE VERY WELL UNTIL YANG
YANG CHANGE -- COULD IDENTIFY
FOUR DISTINCT FOLDING
INTERMEDIATE.
YOU SEE ONE OF THE DOMAINS
FORMED.
ALL ARE INTERACTING WITH THAT
POSITIVELY CHARGED SITE OF THE
CLOSED CHAMBER THAT I MENTIONED.
THEN WE SEE ANOTHER DOMAIN
FORMED IN INTERMEDIATE TWO AND
ANOTHER IN THREE AND FULLY
FOLDED YOU CAN SUPER IMPOSE IT
WITH A CRYSTAL IN INTERMEDIATE
FOUR.
NOW TRIC DOES NOT FOLD IT BY
RELEASING IN IT THE CHAMBER.
BY HOLDING ON TO EACH ONE OF THE
DOMAINS AND ORGANIZING THIS
STRUCTURE OF THE PROTEIN.
SO HERE IN STATE ONE THE IN
TERMING OF DOMAIN IS FOLDED AND
INTERACTING THROUGH THE
INTERACTIONS.
THE POSITIVE WALL AND THEN THE
-- -- WHICH IS NEGATIVELY
CHARGED IS ALSO INTERACTING WITH
THE POSITIVITILY INTERACTING.
ORGANIZING THE TOP ALLERGY OF
THE * OF THE SUBSTRATE.
AND TO THE VERY TIP OF THE -- --
IN THE NEXT INTERMEDIATE THE --
HAS FOLDED AND IT ALSO
INTERRUPTS WITH THE POSITIVELY
CHARGED SIDE OF THE WALL.
SO NOW THE TOPOLOGY -- THIS
LOOKS LIKE NATIVE AND THE MIDDLE
OF THE PROTEIN WE CANNOT SEE IT.
WE KNOW FROM CROSS LINKING IT'S
INTERESIT'SINTERACTING.
SO IN STATE THREE YOU SEE THIS
LITTLE CORE IS BECOMING FORMED
AND NOW WE SEE GTB BINDING TO
THIS NASENT CONFORMER.
*.
SO I THINK THIS IS VERY EXCITING
BECAUSE IT SUGGEST THAT TUBE
LEAN TAR STAR THAT IS A PROTEIN
THAT CAN ONLY FOLD WITH THE
ASSISTANCE OF TRIC IS NOT REALLY
FOLDING.
IT'S FOLLOWING THE DYNAMIC
POTENTIAL.
WHAT WE SPECULATE ALTHOUGH WE
DON'T KNOW BECAUSE WE HAVE NOT
DONE THE BIOPHYSICAL
MEASUREMENTS IS PERHAPS THE
NATIVE STATE IS NOT ONE OF THE
MOST STABLE STATES.
AND WHAT TRIC IS DOING IS BY
THIS SPECIFIC INTERACTION WITH
THE CHAMBER IT'S ACTUALLY
DIRECTING THE DIFFERENT FOLDING
INTERMEDIATES ALONG THE FOLDING
PATHWAY.
ONE THING THAT IS INTERESTING
THERE IS BACTERIA AND IT HAD
LONG BEEN RECOGNIZED THAT THE
DIFFERENCE BETWEEN -- BACTERIA
IS WHERE ALL OF THESE INSERTIONS
ON THE SURFACE OF THE PROTEIN.
THEY INTERACT WITH THE WALL OF
THE CHAMBER THAT LEADS -- THEM
TO FALL.
THIS IS VERY EXCITING TO THINK
ABOUT HOW SOME PROTEINS EVOLVE
AND PERHAPS THE NEW FUNCTIONS OF
TUBE LEAN * AND IT CO-EVOLVED
WITH TRIC TO BE ABLE TO FOLD
WHILE ACQUIRING THESE NEW
FUNCTIONS AND THIS IS A
FASCINATING TOPIC.
I KNOW PATRICK DOLAN LINES TO
THINK ABOUT PROTEIN EVOLUTION.
AND IT IS VERY EXCITING AND KIND
OF LIKE WILL OPEN UP TO THINKING
ABOUT PROTEIN EVOLUTION.
TO FINISH I WANT TO TELL YOU
ABOUT WHAT ARE THE QUESTIONS
THAT WE'RE INTERESTED IN.
WE WANT TO UNDERSTAND HOW TRIC
WORKS FOR OTHER SUBSTRATES.
THERE ARE SOME THAT HAVE THREE
AND FOUR SUB UNITS OF
CHAPERONINS.
HOW TRIC IS REGULATED.
IT'S REDUCED DURING AGING.
SO I THINK THERE COULD BE A LOT
OF INTERESTING THINGS TO DO
THESE.
AND WE RECENTLY COMPLETED A
SMALL MOLECULE REGULATOR SCREEN.
I DIDN'T MENTION THAT TRIC IS
STRONGLY -- REGULATED.
NOW WE WANT TO SWITCH TO WHAT
HAPPENS WHEN PROTEINS CANNOT
FOLD?
I'VE TOLD YOU ABOUT PRODUCTIVE
FOLDING.
WHAT HAPPENS IF A PROTEIN CANNOT
FOLD FOR WHATEVER REASON.
IT CAN EITHER THE SYSTEM CAN
EITHER TARGET IT OR OTHER FORMS
OF DEGRADATION OR KEEP TRYING TO
REFOLD.
SO WE STARTED TO LOOK AT THESE
ALMOST 20 YEARS AGO AND THE
FIRST PERSON WAS AMY
McCLELLAND WHO LOOKED AT A
COUPLE OF MODELS PROTEINS FOR
MISS FOLDING AND THESE ARE ALL
EITHER TEMPERATURE SENSITIVE
PROTEIN OR MU TACT -- OR AN A
SIM BUILD MUTATED TUMOR SUPPRESS
OR.
WHEN THEY MISS FOLD DON'T
AGGREGATE.
THEY JUST GET DEGRADED.
WE WERE ALSO CURIOUS ABOUT
LOOKING AT PROTEINS THAT WHEN
THEY MISS FOLD ACTUALLY
ACCUMULATE AND AGGREGATE.
* THE PROTEINS LOOK VERY
DIFFERENT.
SO WHEN AMY STARTED TO LOOK AT
THIS SHE STARTED WITH THE TUMOR
SUPPRESS OR AND WE KNEW THIS WAS
A PROTEIN THAT TO FOLD NEEDED
TRIC AND THAT IS HOW WE STARTED
TO LOOK AT THIS.
THEY ALSO NEEDED CHAPERONINS TO
GET DEGRADED.
AND THERE SEEMS TO BE A
DEGRADATION CHAPERONE NETWORK
THAT WAS IMPORTANT.
AND OF COURSE THIS WAS
INTERESTING ALSO FROM THE POINT
OF VIEW -- COULD YOU
REFRACTIONAL EYES SOME OF THE
MUTATIONS.
* FAST-FORWARD ANOTHER POSTDOC
IN THE LAB FIGURED OUT WHO WAS
AT THE OO SITE.
HE IDENTIFIED NOT ONLY THAT THIS
CHAPERONES THAT AMY SAW REALLY
PARTICIPATING -- AND ALSO
IDENTIFIED TWO SETS OF -- THAT
NEED TO PRODUCE MIXED LINK
UBIQUITOUS NATION FOR PURPOSES
OF DEGRADATION.
INTERESTING -- THEN GENERATED
NUCLEAR MISS FOLDED PROTEINS AND
IDENTIFIED THE DIFFERENT
CHAPERONE REQUIREMENT AND A
DIFFERENT -- L IgA SE THAT DID
NOT REQUIRE THE LINK BUT
REQUIRED -- TO GET THE PROTEIN
TO THE CYTOPLASM.
THIS IS A SIMPLER SYSTEM.
THE COMPLEXITY OF THIS NETWORK
AND THE THE INTRICACY OF THE
DIFFERENT FACTORS THAT MAKE
DECISIONS ABOUT PROTEIN FATE.
NOW ALL OF THIS EXPERIMENTS YOU
CAN IMAGINE THEM AS HAPPENING IN
THE TESTUD BUT WHEN WE STARTED
LOOK AT IMAGING WHAT HAPPENS TO
MISS FOLDED PROTEINS.
AND THE FIRST PERSON TO DO THIS
IN MY LAB WAS -- LET ME SEE IF I
CAN PLAY THIS MOVIE.
SORRY.
TECHNICAL.
THERE IT IS.
OKAY.
SO THESE ARE TWO DIFFERENT
TEMPERATURE SENSITIVE PROTEINS.
THEY ARE BOTH FOLDED AT THE
BEGINNING OF THE EXPERIMENT AND
THEY ARE DIFFUSED AND FOLDED AND
WHEN THE MOVIE STARTS WE'RE
UNFOLDING THEM BY SHIFTING.
AND THERE'S NO -- PROTEIN
INHIBITION HERE.
YOU CAN SEE THAT -- THEY ARE
ALREADY -- THESE ARE FORMING AND
THE TWO DIFFERENT MISS FOLDED
PROTEINS ARE SEQUESTERED.
THESE ARE NOT AGGREGATES.
THE PROTEIN IS SOLUBLE AND BOUND
TO CHAPERONES.
BUT THIS DOESN'T HAPPEN WITH THE
PROTEIN FLOATING AROUND IN THE
CYTOPLASM.
IT'S SPATIALLY RESTRICT TO
SPECIFIC STRUCTURES IN THE
CYTOPLASM.
SO OVER THE YEARS WORK FROM DON
AND -- HAVE ACTUALLY DEFINED THE
PATHWAY BY WHICH THIS SPATIAL
SEQUESTATION HAPPENS.
WE SEE THAT EVEN IN THE ABSENCE
OF ANY TYPE OF STRESS THIS -- --
THEY COALESCE AND EVEN AS THEY
GET DEGRADED AND THEY END UP IN
THE VICINITY OF THE NUCLEAR
INVOLVED.
SOLUBLE PROTEINS ARE SEQUESTERED
IN A DIFFERENT INCLUSION.
WHEN THE SYSTEM IS OVERWHELMED
AND WE ACTUALLY EITHER INHIBIT
-- AND THERE IS STRESS GOING ON
THEN THIS LEADS TO A STRUCTURE
CALLED THE JUNK AND RECENTLY --
ACTUALLY SHOWED THAT THIS JUNKS
NOT ONE BIG INCLUSION BUT A
COLLECTION OF SMALL CUBICLES ALL
COALESCING.
SO BECAUSE OF THIS EXPERIMENT WE
CAN START TO UNDERSTAND WHAT IS
THE FUNCTION OF THESE SPATIAL
SEQUESTATION.
AND THIS WAS WORK DONE BY OUR
POSTDOC IN THE LAB WHO
IDENTIFIED SMALL -- PROTEINS AS
REQUIRED FOR -- FOR --
FORMATION.
* I'LL PLAY A MOVIE WHERE WE DO
THE SAME EXPERIMENT BUT IN A --
STRAIN LACKING THE PROTEIN.
YOU WILL SEE THERE IS NO
COALESCENCE.
HOWEVER THE PROTEIN STILL GETS
DEGRADED.
THE CELLS ARE STILL RESISTANT TO
STRESS SO YOU DON'T NEED THIS
FOR DEGRADATION OR STRESS
RESISTANCE.
SO WE WERE WONDERING WHY DO YOU
NEED SPATIAL SEQUESTATION IF YOU
DON'T NEED IT FOR DEGRADATION.
AN EXPERIMENT THAT STEPHANIE DID
IS A COMPETITION EXPERIMENT
WHERE WE MISSED 50% CELLS AND
50% OF MUTANTS -- -- IF WE USE
HSP26 WHICH IS IRRELEVANT TO THE
PROCESS THEN WE GREW THEM FOR
SEVERAL GENERATIONS AND WITH ASK
WHO WINS?
NOBODY WINS.
THE RELATIONSHIP OF MUTANT TO --
IS MAINTAINED.
WHEN WE DO THIS FOR THE --
PROTEIN UNDER NO STRESS
CONDITIONS SAME THING.
7 DOESN'T REALLY MATTER BUT WHEN
WE PUT THE CELLS UNDER STRESS
THE CELLS THAT CANNOT FORM THE
SPATIAL SEQUESTATION OF MISS
FOLDED PROTEINS ARE LESS FIT AND
ARE OUTCOMPETED BY THE WILD
TYPE.
SO THE CONCLUSION OF THESE IS
THAT SPECIFIC CHAPERONE PATHWAYS
-- CLEAR DECISIONS IN THE CITE
PLASM AND THEY ARE DIFFERENT.
THAT PROTEIN QUALITY CONTROL IS
SPATIALLY ORGANIZED AND THAT
SPATIAL SEQUESTATION IS A
PROTECTIVE MECHANISM.
AND SO SHOW YOU THIS HAS SOME
RELEVANCE I WANT TO BRING UP
SOME EXPERIMENTS WHERE THEY
COLORADO COLLABORATED -- AND TO
OUR SURPRISE IF YOU DO THESE YOU
CAN SEE A BIG INCLUSION AND THEN
YOU SEE WHAT IS REFERRED TO IS A
SOLUBLE DIFFUSED FLUORESCENCE.
THEY FOUND ACTUALLY THERE WAS NO
SOLUBLE DIFFUSED FLUORESCENCE.
IT IS A SERIES OF SERIES OF
SMALL STRUCTURES.
THEY ARE NOT BIG INCLUSIONS BUT
THEY DO LOOK SMALL IN NATURE.
AND IN COLLABORATION WITH LESLIE
THOMPSON WE HAD DEVELOPED A
CHAPERONE STRATEGY TO RESCUE THE
TOXICITY AND WHEN WE ADDED THESE
EXPRESSING MUTANT HUNTINGTON AND
SUBJECTED THEM WE FOUND THAT
THIS CHAPERONE DOMAIN LONG STORY
AND I CAN TELL YOU MORE BUT THIS
IS A CHAPERONE THAT SUPPRESSES
HUNTINGTON TOXICITY PRIMARILY
REDUCE THE AMOUNT OF THE SOLUBLE
DIFFUSED LITTLE STRUCTURES.
WHICH AGAIN SUGGEST THAT PERHAPS
SEQUESTATION IS A PROTECTIVE
PATHWAY.
SO BASICALLY WE'RE INTERESTED IN
UNDERSTANDING THE PATHWAYS THAT
PROMOTE QUALITY CONTROL
OBVIOUSLY THE BIG QUESTION IS
WHY IS THERE TOXICITY FROM THESE
FOLDED PROTEINS AND WE'RE VERY
INTERESTED IN LOOKING FORWARD
ABOUT THIS STRUCTURE OF THESE
INCLUSIONS.
7 HOW MUCH MORE TIME DO I HAVE?
OKAY.
SO I'M GOING TO GIVE YOU A A
LITTLE -- ALL OF THIS STUFF SO
FAR WE TRY TO UNDERSTAND BASIC
PRINCIPLES BUT AS YOU KNOW -- IT
IS REGULATED IN MANY INTERESTING
WAYS AND THAT COULD BE USEFUL
FOR THERAPEUTICS.
THESE ARE A NUMBER OF THINGS
THAT WE HAVE BEEN INTERESTED IN
THE LAB.
WE'RE VERY INTERESTED IN
UNDERSTANDING AND APPLYING OUR
BASIC UNDERSTANDING TO TOXICITY
DURING NEURODEGENERATION AND WHY
-- IT DECLINES DURING AGING AND
HOW CAN THESE DECLINES SYNERGIZE
AND -- FOR MANY YEARS AND
COLLABORATION TO TRY TO
UNDERSTAND HOW VIRUSES -- AND
CAN WE EXPLOIT THAT FOR
THERAPEUTIC PURPOSES.
7 SO I'LL MENTION A COUPLE OF
THINGS WITHOUT GOING INTO A LOT
OF DETAIL.
ONE OF -- HAS BEEN TRYING TO
UNDERSTAND HOW THE PROCESS OF
TRANSLATION COUPLED FOLDING AND
BIOGEN SIS IS IMPACTED BY
DISEASE AND YOU CAN THINK OF THE
* RIBOSOME AS A SUPER MOLECULAR
PROTEIN MACHINE.
WE HAVE A PAPER SHOWING THAT --
HUNTINGTON DISEASE PROMOTES
TRANSLATION DISFUNCTION AND
PROMOTES WIDESPREAD RIBOSOME --
THAT IS TOXIC.
AGING ALSO DISRUPTS -- AND THIS
LEADS TO PROTEIN -- ---AND LAST
YEAR -- SHOWED THAT FOR A NUMBER
OF DIFFERENT VIRUSES THE
INFECTION TOTALLY REMODELS THE
TRANSLATIONAL APPARATUS AND
THERE ARE SOME MODULES SUCH AS
TRANSLATION INITIATION --
QUALITY CONTROL THAT ARE EVICTED
FROM THE RIBOSOME AND SPECIFIC
CHAPERONES THAT ARE RECRUITED TO
RIBOSOMES DURING VIRAL INFECTION
AND THE INTERESTING ASPECT OF
THE WORK IS THAT THE ENTIRE
COLLAGEN -- MACHINERY IS
HIGHJACKED BY VIRUSES TO HELP
PROMOTE THE -- AND IF YOU
INHIBIT THIS MACHINERY HALF OF
THE VIRAL PROTECT TEEN MISS
FOLDS.
* * I'M GOING TO SKIP THE AGING
PART.
WHEN WE COMPARE -- THE PROTEINS
THAT WERE PREVIOUSLY IDENTIFIED
TO AGGREGATE WITH AGING WORMS WE
SEE HIGH LEVELS OF CORRELATION.
SO WE'RE NOW HYPOTHESISSING --
ONE OF THE REASONS THAT YOU SEE
ENHANCED DEGRADATION.
I'LL FINISH WITH SOME TAKE HOME
MESSAGES.
I HOPE I CONVINCED YOU THAT THE
MACHINERY PROFOUNDLY INFLUENCES
PROTEIN FATE.
IT KEEPS MUTANT PROTEINS
FUNCTIONAL.
IT PREVENTS AGGREGATION.
THIS IS GOOD IN A YOUNG PROTECT
YUM.
* IT CAN BE BAD IN A CANCER
CELL.
IF YOU INHIBIT THE CAPACITY AND
YOU CAN THINK OF THESE AS BEING
IN AGING WHERE YOU NOW START TO
SHOW THE PHENOTYPES OF THE
MUTANTS THAT WE HAVE AND THE
MACHINERY KEEPS FUNCTIONAL OR
WHEN YOU INTERVENE WITH DRUGS TO
TREAT VIRUSES OR CANCER YOU WILL
AGGREGATE OR CAUSE DEGRADATION
OF MANY THESE PROTEINS.
I THINK THIS CAN BE A VERY POW
POWERFUL SYSTEM.
WE NEED TO GET PAST THINKING
THAT THE MUTATION OR THE PROTEIN
IS JUST A FUNCTION OF ITS OWN
STABILITY.
IT'S A COMBINES OF ITS OWN
STABILITY AND THIS I TOOK FROM A
REVIEW FROM JEFF KELLY -- AND
THE CONDITIONS IN THE CELL SO
THE LEVEL OF CHAPERONES WILL ALL
KEEP THE PROTEIN WITHIN ITS
FUNCTIONAL RANGE.
SO IN THINKING ABOUT THIS -- WE
CANNOT THINK ABOUT THIS IN
SIMPLISTIC WAYS.
WE NEED TO THINK ABOUT THE DECAY
AS A VICIOUS CIRCLE -- WORKING
TOGETHER WITH AGING TO INCREASE
AGGREGATION AND INCREASE PROTEIN
DYSFUNCTION BECAUSE THERE IS
THIS -- CAPACITY -- THE VICIOUS
CIRCLE GOES AHEAD AND MAYBE I'LL
JUST END BY SAYING THAT IN THIS
LIGHT -- THE PRESENCE OF
AGGREGATES IN AN AGE -- DECEASED
CELL MAY NOT BE THE PROBLEM.
IT MAY BE AN EMERGING PROPERTY
OF DYSFUNCTIONAL -- MACHINERY.
IN A YOUNG CELL YOU HAVE MANY
OPTIONS WHERE YOU HAVE MISS
FOLDED PROTEINS AND AS THE CELL
AGES AND THE CAPACITY GOES DOWN
THEN THE ONLY FUNCTION IS A
SEQUESTATION AND YOU MAY BE LEFT
WITH THIS TYPE OF AGGREGATE.
WE'RE INTERESTED IN
UNDERSTANDING THE BASIC ASPECT
OF THE FUNCTION OF THE MACHINERY
AND ALSO UNDER HOW IT GOES.
I'LL ACKNOWLEDGE ALL OF THE
PEOPLE THAT DID THE WORK.
I THINK I MENTIONED EVERYBODY.
THESE ARE THE MAIN CONTRIBUTORS.
I HAVE TO ACKNOWLEDGE OUR
COLLABORATORS.
AND I REALLY NEED TO THAT AND
NIH FOR FUNDING.
IT'S PAINFUL BUT WITHOUT IT
NOTHING OF THIS COULD HAPPEN SO
I HAVE TO THANK THEM ALL THAT
GAVE US MONEY TO DO THIS WORK.
[ APPLAUSE ]
>> THANK YOU AND ANYONE HERE IS
FREE TO USE THE MICS.
WE HAVE SEVERAL QUESTIONS COMING
IN.
ONE IS A COMMENT THAT JUST CAME
NCATS PLEASE INVITE HER BACK TO
TEACH US MORE ABOUT AGING AND
THE SLIDES SHE JUST TEASED US
WITH.
MADE MY DAY.
GIVE HER A ROUND OF APPLAUSE.
>> THIS IS FANTASTIC.
THANK YOU SO MUCH.
AND I HOPE I DIDN'T MISS IT BUT
I WAS STRUCK BY YOUR STRUCTURES
AND FOLDING -- AND I WAS
WONDERING 10% OF HUMAN PROTEINS
ARE USING THE SAME KIND OF
MECHANISM.
SO ARE THEY STRUCTURALLY THE
SAME OR IS THERE STRUCTURAL --
IN TRIC.
CAN YOU COMMENT ON HOW YOU
ENVISION THAT WORKING?
>> THAT IS A VERY GOOD QUESTION
AND A LOT OF THINGS TO THINK B.
WE HAVE THE STRUCTURE OF TUBE
LEAN * AND WE HAVE AN ONGOING
STRUCTURE OF ACTING SO, THAT IS
THE EXTENT OF MY UNDERSTANDING
OF FOLDING INTERMEDIATES.
WE HAD PUBLISHED A PAPER -- SO
IT -- PROTEIN FROM REAL VIRUSES
ALSO NEEDS TRIC TO FOLD.
ACTUALLY BINDS TO DIFFERENT
REGIONS WITHIN THE CHAMBER.
MAYBE DIFFERENT PROTEINS THAT
NEED TRIC TO FOLD WILL INTERACT
WITH DIFFERENT REGIONS AND MAYBE
THIS IS WHAT THE -- -- DID IT
GENERATED THE POSSIBILITY THAT
DIFFERENT PROTEINS WILL BIND IN
DIFFERENT REGIONS.
WITH THAT SAID A LARGE NUMBER OF
TRIC SUBSTRATES THAT WE SEE
DIRECTLY -- PROBABLY ALL THEY
NEED IS -- CHAPERONE.
SO A LOT OF PROTEINS --
---ENZYMES WHOSE BACTERIAL HOMO
LOGS -- SO FOR THE EVOLUTION OF
TRIC IT'S NOT THAT TRICKS
INVOLVED -- TUBE LEAN * AND
OTHER SUBSTRATES EVOLVED AS TRIC
DIVERSITY FIGHTERS -- TO USE
SPECIFIC FEATURES OF THE CHAMBER
OF THE SUBSTRATE BINDING SITE OF
THE TAILS.
BUT TRIC ALSO MAINTAIN THE
ABILITY TO BIND AND ENGULF
CHAPERONES AND WHAT THEY NEED IS
TO BIND AND FALL TO THE NATIVE
STATE AND BE FOLDED.
SO I DON'T THINK EVERY PROTEIN
THAT INTERACTS IS AN OBLIGATE
SUBSTRATE.
WHEN WE LOOK AT HOW THEY BIND 6
THESE ARE COMPLETELY DIFFERENT
PROTEINS BY TRIC BINDS IN THE
SAME PLACE OF THE BARREL OF THE
BLADES.
SO I THINK THERE ARE A LOT OF
VERY COOL QUESTIONS.
>> THANK YOU.
>> TWO QUESTIONS ON-LINE.
BECAUSE IT MIGHT BE RELATED
TOGETHER IN WHAT HE JUST ASKED.
FIRST IS WHAT IS THE FOLDING
COMPLEXITY OF THE CHAPERONE
PROTEINS?
DO THEY ALSO REQUIRE CHAPERONS
FOR FOLDING?
AND DO ALL-PRO TEENS FOLDED BY
THE TRIC CHAPERONE SHARE A
SIMILAR STRUCTURE THAT ALLOWS
TRIC TO MONITOR FOLDING AND A
SIMILAR MECHANISM FOR ALL
SUBSTRATES
SOME OF THEM AT LEAST ALSO NEED
CHAPERONES.
WE KNOW THAT --
CO-TRANSLATIONALLY.
THEY ALSO NEED -- THEY ARE JUST
PROTEINS LIKE OTHER PROTEINS MAY
NEED CHAPERONES TO FOLD.
WITH REGARD TO TRIC YES THERE
ARE SOME DOMAINS THAT ARE OVER
REPRESENTED IN TRIC.
SO THE BETTER PROPELLER -- 40
PROTEINS -- WHICH TUBE LEAN AND
OKAY TEEN HAVE -- FOLDS *.
LOTS OF RNA AND DNA BINDING
PROTEINS.
THEY SEEM TO ME TO BE ABLE TO
FOLD.
BUT THERE ISN'T ONE TYPE OF
DOMAIN.
THERE ARE OTHER PROTEINS THAT
DON'T NEED TRIC.
IT'S NOT JUST THE FOLD.
THERE MUST BE ELEMENTS THAT --
INTERFERE WITH THE FOLDING
PATHWAY.
THAT MAKE THEM NEED TRIC.
>> AWESOME.
MY QUESTION IS ALSO ABOUT TRIC.
WITH SO MANY DIFFERENT FOLDING
SUBSTRATES HOW DOES TRIC KNOW
WHEN EACH PEPTIDE IS DONE
FOLDING?
HOW DOES IT SENSE?
IS IT ON A TIMER?
DOES A FOLDED PROTEIN -- WHAT IS
AUGMENTED?
>> HMMM.
GOOD QUESTION.
SO THE CYCLE -- OF TRICKLE POSES
A TIMER.
WE CECE THIS -- THIS WOULD BE
NICER DONE IN VERY VOTE BUT
WE'VE DONE INVITRO EXPERIMENTS
THAT SUGGEST -- PROBABLY AFTER
THAT THEY GET DEGRADED.
BUT THERE IS SOME PROTEINS THAT
THEY FOLD AND THEY STAY BOUND TO
TRIC.
SO MANY SUBSTRATES ARE -- OF
LARGE COMPLEXES.
FOR THOSE THERE MUST BE A
MECHANISM TO KICK THEM OFF.
EITHER THE PARTNER COMES IN AND
THEY BIND TO THE PARTNER OR
SOMETHING LIKE THAT.
YEAH.
IN PRINCIPLE YOU COULD IMAGINE
THAT FOR CHAPERONES -- THE
REGIONS THAT ARE BURIED INSIDE
THE PROTEIN -- THE PROTEIN
DOESN'T INTERACT ANY MORE BUT
WITH TRIC INTERACTS ON THE
SURFACE.
HOW IT IS RELEASED IS AN
INTERESTING QUESTION.
>> I'M CURIOUS ABOUT SPATIAL
REGULATIONS AT THE QUALITY
CONTROL.
AND NORMALLY WE KNOW THAT THE
CHAPERONES FUNCTION TO PREVENT
PROTEIN TO PREVENT AGGREGATION.
CAN YOU ELABORATE MORE ON HOW
WHAT IS THE UNDERLYING
MECHANISM.
>> SO I DON'T KNOW.
BUT ONE THING THAT IS VERY COOL
ABOUT -- PROTEINS IS THEY HAVE
-- CRYSTALLINE DOMAIN AND THEY
HAVE LONG -- ---AND WORD FROM
RACHAEL HAS SHOWN THAT THESE --
-- INTERACT WITH THE CRYSTALLINE
DOMAIN SO THEY FOLD BACK IN AND
MAYBE ACTIVATE SUBSTRATE BINDING
SO ONE POSSIBILITIES THAT WHEN
THE SUBSTRATE BINDS -- THESE
OPEN UP AND THEY FORM SOME SORT
OF MeSH WORK SO IT'S NOT
APPEAR AN AGGREGATE.
IT'S COMPLETELY SOLUBLE BUT THEY
FORM A MeSH WORK WITH THE
SUBSTRATE THAT FORMS SOME SORT
OF CONDENSATE.
I HATE THAT WORD BUT SOMETHING
LIKE THAT.
-- EXPRESSED ALL OF THE HUMAN
SMALL -- PROTEINS IN THE
DELETION AND SHOWED THAT SOME OF
THE THEM CAN DESTROY THE
PHENOTYPE.
THIS COULD BE A GENERAL
PROPERTY.
>> WELL THANK YOU VERY MUCH.
WE HAVE TO CUT IT OFF HERE.
>> YOU CAN E-MAIL ME YOUR
QUESTIONS.
I WILL BE HAPPY TO ANSWER THEM.
>> THANK YOU.
IT'S A WONDERFUL TALK.
THANK YOU VERY MUCH.
[ APPLAUSE ]