homologous recombination - 2025 ACF Nationals

Tossup

A class of enzymes that perform this process with a catalytic serine residue is exemplified by Bxb1 and PhiC31 (10[1])and is used to deliver large cargo. An enzyme that performs this process is delivered alongside various fluorescent proteins to visualize the connectome in Brainbow imaging. This process can be encouraged by knocking out Ku·70 and Ku·80 (10[1])to inhibit a different process from competing with this one during CRISPR knock-in experiments. This process is (10[1])performed by a non-chaperone (10[1])enzyme that, when attached to an estrogen receptor, creates an inducible (10[1])gene expression system controlled by tamoxifen. This process is localized to LoxP sites (10[2])in a site-specific (10[1])variant (10[1])of this process (10[2])driven by (-5[1])the enzyme Cre (-5[1])(“cree”). For 10 points, name this process in which two homologous strands of DNA exchange sequences (10[2])with (10[1])each other. (10[1])■END■ (10[3]0[3])

ANSWER: homologous recombination [accept HR; accept recombinases or Cre recombinase; accept large serine recombinases; accept genetic recombination; accept recombineering; accept crossing over; accept homology-directed repair; prompt on insertion or integration; prompt on DNA repair or double-strand break repair or DSB repair]

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Buzzes

Player	Team	Opponent	Position	Value
Jason Zhang	Toronto C	RIT	18	10
Sharath Narayan	Northwestern	Stanford	55	10
Bryan Ugaz	Arizona State	Waterloo B	72	10
Raymond Chen	Toronto B	Winona State	76	10
Collin Nadarajah	WUSTL B	Columbia A	87	10
David Bass	Johns Hopkins	Georgia State	100	10
Annabelle Yang	WUSTL A	MIT	100	10
Andrew Wang	Illinois A	Virginia	103	10
Richard Niu	Cornell A	Ottawa	104	10
Tony Chen	Toronto A	Georgia Tech	107	10
Ryan Rosenberg	NYU	Penn State	107	10
Tiffany Zhou	Florida	Illinois B	109	-5
Alan Xie	Yale	Cornell B	112	-5
Joel Miles	Minnesota	Michigan	127	10
Shiva Tegulla	UCF	Ohio State	127	10
Andy Huff	LSE	Vanderbilt	128	10
Soren Heydari	North Carolina B	Texas	130	10
Yash Mandavia	Illinois B	Florida	131	0
Alex Akridge	Indiana	Iowa State	131	10
Michael Kearney	Harvard	Maryland	131	0
Andy Yu	Maryland	Harvard	131	0
Liam Kusalik	Waterloo A	North Carolina A	131	10
Julian Bushlow	Cornell B	Yale	131	10

Summary

Tournament	Exact Match?	TUH	Conv. %	Power %	Neg %	Average Buzz
2025 ACF Nationals	Yes	20	90%	0%	10%	101.89