# Construction and Expression Analysis of the bin 3xOllas Tool Line

## TL;DR

Scientists created a new fruit fly line to track a protein called Bin, which helps study its role in development and reproduction.

## Contribution

A new Drosophila knock-in line with a 3×Ollas tag at the biniou locus for precise visualization of the Bin transcription factor.

## Key findings

- The bin 3xOllas allele shows native expression in visceral mesoderm without disrupting Bin function.
- Bin is expressed in adult reproductive tissues like ovarian escort cells and testis hub and cyst cells.

## Abstract

Precise detection of endogenous protein expression is essential for understanding gene function
in vivo
. We generated a
Drosophila
knock-in line inserting a 3×Ollas tag at the C-terminus of the endogenous
biniou
(
bin
) locus, enabling specific visualization of the Bin transcription factor. The

bin
3xOllas

allele faithfully recapitulates native expression in the visceral mesoderm and does not disrupt Bin function. Integrating single-cell RNA-sequencing data, we further identified Bin expression in adult reproductive tissues, including ovarian escort cells and testis hub and cyst cells. This allele provides a robust tool for studying Bin function and dynamics.