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>> GOOD AFTERNOON, EVERYONE.
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THIS IS A SPECIAL DAY BECAUSE WE
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ARE IN THE FIRST DAY OF THE NIH
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RESEARCH FESTIVAL AND A SPECIAL
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DAY BECAUSE WE HAVE A REMARKABLE
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LECTURER AS PART OF OUR REGULAR
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WEDNESDAY AFTERNOON SERIES WHO
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IS HERE TO TEACH US SOMETHING
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PRETTY INTERESTING ABOUT VIRAL
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HEMORRHAGIC FEVER, SPECIFICALLY EBOLA VIRUS.
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ERICA OLLMANN SAPHIRE HAS AN
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INTERESTING AND VERY PRODUCTIVE
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CAREER BRINGING HER TO WHERE SHE
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IS A PROFESSOR IN IMMUNOLOGY AND
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MICROBIAL SCIENCE AT THE SCRIPPS
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RESEARCH INSTITUTE.
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WE FOUND A PROFILE OF HER IN THE
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SAN DIEGO UNION TRIBUNE WHERE
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SHE WAS CALLED, THE VIRUS
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HUNTER.
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AND VARIOUS COMMENTS WERE MADE
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ABOUT HER CONTRIBUTIONS, WHICH
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ARE OBVIOUSLY SUBSTANTIAL.
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I WON'T COMMENT UPON WHAT THEY
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CALLED HER, ALIAS, STEEL
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MAGNOLIA.
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I THOUGHT THAT WAS ODD TO BE
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PUTTING IN A PROFILE OF A
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SCIENTIST BUT YOU CAN DECIDE FOR
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YOURSELF.
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SHE GOT HER UNDERGRADUATE DEGREE
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AT RICE WITH A DOUBLE MAJOR IN
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BIOCHEM AND CELL BIOLOGY AND
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ECOLOGIY AND EVOLUTIONARY
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BIOLOGY AND PH.D. AT THE SCRIPPS
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IN THE YEAR 2000.
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AND HAS BEEN THERE IN THIS
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REMARKABLE PRODUCTIVE ENTERPRISE
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FOCUSED ON TRYING TO UNDERSTAND
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HOW PATHOGENS EVADE AND USURP
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THE INNATE AND ADAPTIVE IMMUNE
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RESPONSES.
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SHE HAS QUITE A DIVERSITY OF
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PROJECTS GOING ON IN THE LAB
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INCLUDING LASSA AND MARRER AND
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EBOLA FEVER AND SHE IS AN EXPERT
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IN INCORPORATING DIFFERENT
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APPROACHES TO INTERESTING THIS
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INCLUDING IMFROG NOLOGY AND
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EXTRA CRYSTALLOGRAPHY --
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IMMUNOLOGY -- AND I WANT TO
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POINT OUT AT THE END OF THE
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LECTURE, WE WILL HAVE TIME FOR
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QUESTIONS AND THE MICROPHONES
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ARE IN THE AISLE AND WELCOME TO
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THOSE OF YOU WHO ARE WATCHING ON
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THE WEB.
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WE'LL TRY TO BE SURE THAT
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QUESTIONS ARE POSED FROM THE
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MICROPHONE SO YOU CAN HEAR THEM
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AND THEN AT 4:00, WE'LL ADJOURN
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DOWN THE HALL FOR CONTINUATION
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OF INFORMAL CONVERSATIONS WITH
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OUR SPEAKER BUT ALSO THE ACTUAL
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FORMAL UNVEILING OF THE NEW FAES
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CENTER, WHICH I THINK YOU'LL
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WANT TO COME AND HAVE A LOOK AT
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BECAUSE IT IS REALLY QUITE
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BEAUTIFUL FACILITY AND WE'LL
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HAVE A RIBBON CUTTING AND A FEW
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HOPEFULLY SHORT SPEECHES AND
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THAT WILL MORPH INTO A POSTER
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SESSION WHERE THE SCIENTIFIC
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DIRECTORS WHO ARE THEMSELVES
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STANDING BY THEIR POSTERS
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TALKING ABOUT THEIR SCIENCE
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GIVING YOU A CHANCE TO HAD THE
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THEM UP WITH REALLY HARD
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QUESTIONS.
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SO IT WILL BE QUITE AN
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AFTERNOON.
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BUT, TO GET US GOING HERE, IN MA
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SUR, LET ME ASK YOU PLEASE TO,
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GIVE A WARM WELCOME TO ERICA
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OLLMANN SAPHIRE.
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[ APPLAUSE ]
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>> THANK YOU, DR. COLLINS.
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IT'S A REAL PLEASURE TO BE HERE.
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MY LABORATORY WORKS ON A LOT OF
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DIFFERENT VIRUSES.
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TODAY I'M GOING SHOW YOU CHAMPS
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FROM TWO OF THEM.
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THE FIRST ONE IS EBOLA VIRUS, A
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LONG VIRUS AND THE SECOND ONE IS
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A SMALLER ROUNDER PARTICLE AND
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IT BELONGS TO THE ARENA VIRUS
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FAMILY.
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WHAT THEY HAVE IN COMMON IS A
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SIMILAR DISEASE.
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THEY BOTH CAUSE HEMORRHAGIC
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FEVER AND THE SYMPTOMS LOOK
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SIMILAR ESPECIALLY AT FIRST.
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WHEREAS EBOLA IS QUITE RARE,
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LASSA IS UNFORTUNATELY EXTREMELY
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COMMON.
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THERE ARE HUNDREDS OF THOUSANDS
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OF CASES EVERY YEAR IN WESTERN
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AFRICA AND THE FEVER IS MOST
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FREQUENTLY IS IMPORTED TO THE
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UNITED STATES AND EUROPE.
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NOW WHAT ELSE THESE VIRUS VS. IN
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COMMON IS A VERY SMALL GENOME.
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EBOLA ENCODES SEVEN GENES LASSA
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ONLY 4.
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SO WHERE YOU HAVE 25,000 GENES
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AND YOU CAN MAKE 25,000
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PROTEINS, THESE VIRUSES MAKE
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ONLY A FEW.
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SO, USING THIS VERY LIMITED
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PROTEIN TOOLKIT, HOW DOES A
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VIRUS ACHIEVE ALL THE DIFFERENT
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FUNCTIONS OF THE VIRUS LIFE
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CYCLE FROM ATTACH WANT TO A NEW
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HOST CELL, FUSION AND ENTRY AND
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ENCODING AND TRANSCRIPTIONS AND
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ASSEMBLY AND EXIT AND SOME OF
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THE MORE SOPHISTICATED FUNCTIONS
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FOR LOTS OF DIFFERENT PATHWAYS.
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HOW DO THEY DO THAT?
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ONLY A VERY FEW PROTEINS AT
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THEIR DISPOSAL.
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THIS IS THE GENOME OF LASSA
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VIRUS.
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THOSE ARE -- THAT WAS EBOLA AND
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THIS IS LASSA.
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SO HOW DOES A HANDFUL OF
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PROTEINS CONSPIRE TO CREATE SUCH
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EXTRAORDINARY PATHOGENESIS IN
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HEMORRHAGIC FEVER?
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THE ANSWER IS THAT EACH PROTEIN
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THESE VIRUSES DO ENCODE IS
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ESSENTIAL.
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THESE VIRUS VS. NO JUNK.
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MANY OF THESE PROTEINS ARE
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MULTI-FUNCTIONAL AND SOME ARE
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EXTREMELY ADAPTABLE.
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BY STUDYING THE PROTEINS THESE
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VIRUSES MAKE, WE SEE THE
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VULNERABILITIES OF THE VIRUS,
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THE ACHILLES HEEL, THE PLACE TO
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TARGET A DRUG OR VACCINE OR
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ANTIBODY.
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BUT PERHAPS MORE IMPORTANTLY, WE
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CAN UNDERSTAND SOMETHING MORE
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ABOUT PROTEINS THEMSELVES.
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BECAUSE EVOLUTION HAS COMPELLED
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THESE PROTEINS TO BE REMARKABLE,
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TO DO MORE WITH LESS THAN OTHER
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PROTEINS BY STUDYING WHAT THESE
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PROTEINS ARE CAPABLE OF, WE
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LEARN ABOUT THE CAPABILITIES OF
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PROTEINS IN MOLECULAR BIOLOGY.
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SO I'LL SHOW YOU A FEW EXAMPLES.
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THE FIRST ONE COMES FROM THE
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FIRST STEP OF THE VIRUS LIFE
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CYCLE.
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SO THE FIRST STEP, THE VIRUS HAS
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TO FIND AND ATTACH TO A NEW HOST
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CELL.
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THIS IS ACHIEVED BY THE
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GLYCOPROTEIN CALLED GP.
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BOTH VIRUSES EXPRESS ONLY ONE
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PROTEIN ON THE SURFACE CALLED GP
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AND IT IS SOLELY RESPONSIBLE FOR
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ATTACHING WITH THAT CELL.
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SO EBOLUS VIRUS FILAMENT US.
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THIS HAS A MEMBRANE OF GREEN
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SURROUNDING A NUCLEO CAP SID.
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AND THERE ARE SPIKES.
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THOSE ARE FORMING 450
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KILLADALTON TRIMERS AND THEY ARE
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QUITE HEAVILY GLYCOSYLATED.
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SO THE QUESTION YOU MIGHT ASK
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IS, IF THIS SPIKE IS IMPORTANT
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FOR ATTACHMENT AND ENTRY, WHAT
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DOES IT LOOK LIKE AND HOW DOES
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IT WORK?
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WE HAD TO MAKE ABOUT 140
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VERSIONS OF THIS GP TO GET ONE
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THAT WOULD CRYSTALLIZE WELAND WE
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HAD TO THROW BACK 150.
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BEFORE WE HAVE A STRUCTURE, WE
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THINK OF A PROTEIN WITH AN END
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TERMINUS AND C TERMINUS.
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THIS IS CLEAVED IN THE PRODUCER
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CELL, WITH 2 SUB UNITS.
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A GP1 WHICH MEDIATES THE
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RECEPTOR BINDING AND GP2 WHICH
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MEDIATES FUSION.
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SO THE BP1 HAS RECEPTOR BINDING
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DOMAINS AND THE GP2 HAS TO
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UNDERGO A CHANGE.
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ALSO IN GP1 IS THIS UNUSUAL MUSE
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IN-LIKE DOMAIN IT'S VERY HEAVILY
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GLYCOSYLATED.
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THERE IS A LOT OF UNSTRUCTURED
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PROTEIN HERE.
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SO THIS IS THE CRYSTAL STRUCTURE
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OF THE EBOLA VIRUS GP.
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YOU CAN SEE THE 3GP1 SUBUNITS IN
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BLUE AND GREEN.
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THESE RECEPTOR BINDING ARE TIED
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TOGETHER AT THE BOTTOM BY THE
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GP2 FUSION SUBUNITS.
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NOW THERE IS SOMETHING
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INTERESTING HERE.
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WHEN YOU THINK ABOUT A FUSION
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PEPTIDE OR FLU OR HIV, IT'S A
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HYDROPHOBIC PEPTIDE TUCKED UP
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INSIDE THE STRUCTURE.
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HERE ARE THE FUSION LOOP IT IS
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TACKED ON TO THE OUTSIDE.
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THIS REACHES ALONG THE OUTSIDE
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AND BINDS INTO THE NEXT ONE.
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IN ORDER TO GET THIS TO
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CRYSTALLIZE, WE HAD TO EXIZE AND
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WE WANT TO UNDERSTAND WHAT THE
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REAL GP LOOKS LIKE ON THE
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SURFACE.
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IT HAS HEAVILY GLYCOSYLATED
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DOMAINS ATTACHED AT THE TOP.
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NOTE GP ONE TAINING THAT DOMAIN
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CRYSTALLIZES AND WE HAD TO USE A
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DIFFERENT TECHNIQUE.
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A SMALL SCATTERING, TINY X-RAYS
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AND PROTEIN MOLECULES TUMBLING
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AROUND IN SOLUTION GET A LOW
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RESOLUTION VIEW, MAYBE 10
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RESOLUTION.
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AND THEN THIS, TURNS OUT THIS IS
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THE SOLUTION SCATTERING ENVELOPE
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OF THE GLYCOSYLATED EBOLA VIRUS
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GP.
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SO THE CRYSTAL SHUCK STRUCTURE
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IS IN THE RIBBON CENTER.
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SO THESE ARE THE DOMAINS
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ATTACHED.
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SO THE EFFECTIVELY TRIPLE THE
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SIZE OF THE MOLECULE.
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AND THIS IS A HELL OF A GLYCAN
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SHE WOULD.
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THEY REACH ABOUT 100 FROM THE
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CORE OF THE G.
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AND THEY ARE QUITE FLEXIBLE SO I
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EXPECT THE ACTUAL WILT OF THIS
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DOMAIN TO BE HALF THAT.
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I THINK VISUALIZING THE
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FLEXIBILITY AS WELL.
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THE SALIENT FEATURE OF THIS IS
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THAT THESE MUSE IN-LIKE DOMAINS
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ARE MASSIVE AND THEY DOMINATE
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THE STRUCTURE.
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S OKAY?
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SO THIS IS WHAT IS ON THE
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BIOSURFACE.
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HOW DOES IT WORK?
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HOW DOES IT FIND AND GET INTO A
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NEW CELL?