In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Q: One protein that binds to this protein also binds to proline-rich sequences in the membrane proteins Vasp and Mena, and another is knocked out in the singed mutant. Phosphatidyl-inositol-4,5-bisphosphate regulates the binding of vinculin to both talin and this other protein, whose function is performed by nematode Major Sperm Protein in the only (*) eukaryotic cells known to lack one form of it. In addition to the aforementioned profilin and facsin, severin and gelsolin bind to this protein and sever it. Two toxins often used to study it are cytochalasins and phalloidin. Thymosin 4 sequesters this protein, which undergoes treadmilling because the critical concentration at its (+) and (-) ends is not the same. This protein consists of G monomers which polymerize into F filaments, which make up the microfilaments of the cytoskeleton. For 10 points, name this protein that forms cross-bridges with myosin in muscle cells.

A: Science
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Q: Late in his life, this man attempted to mediate the Burundian civil war. In 1967, he issued a manifesto prohibiting government ministers from renting out houses and proclaiming "let us pray and heed to the peasant. " He negotiated with Richard Turnbull for independence before issuing the (*) Arusha Declaration and merging his country with a nearby island. For 10 points name this man who promoted ujamaa in Tanzania.

A: History
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Q: It regulates the expression of cis-Nat genes in Arabidopsis, and its failure is the cause of the FMR1 mutation in fragile X syndrome. Drosha and Pasha are proteins that disrupt exportin-mediated transport involved in this process, which leaves behind subcomponents that bind to foreign molecules and targets them for the RDE-1 nuclease. Dicer cuts out the stem and loop structure of the double strand precursor to create a single strand template used by the RISC complex to repress translation or destroy messenger templates. Earning a Nobel prize for Andrew Fire and Craig Mello, FTP name this naturally occurring gene silencing process also used by biologists to inhibit gene expression, often using micro RNA or siRNA.

A:
Science
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