# Dual tagging of GFP and Degron on endogenous COSA-1 in Caenorhabditis elegans as a crossover investigation tool

## TL;DR

This study creates a tool to study COSA-1 in C. elegans by enabling its controlled degradation, revealing its role in meiosis.

## Contribution

A novel C. elegans strain with inducible COSA-1 degradation using the AID system was developed.

## Key findings

- Auxin treatment depletes COSA-1, causing a 96% decrease in progeny viability.
- Degradation results in 12 univalent chromosomes in diakinesis oocytes.
- The strain maintains normal fertility and COSA-1::GFP foci before treatment.

## Abstract

COSA-1
is essential for accurate meiosis in
C. elegans
. Two null mutants (

cosa-1
(
me13
)

and

cosa-1
(
tm3298
)

) have been notably studied. These null mutants exhibit severe meiotic defects, hindering the observation of the subtle or dynamic nature of
COSA-1
function. To overcome these limitations, we developed a
C. elegans
strain with inducible
COSA-1
degradation using the Auxin-Inducible Degron (AID) system. This strain exhibits normal fertility and COSA-1::GFP foci. Auxin treatment successfully depletes COSA-1, resulting in a 96% decrease in progeny viability and 12 univalent chromosomes in diakinesis oocytes. This strain serves as a valuable tool for studying the dynamics of COSA-1.