# SAMS-1 is required for the normal defecation motor program in Caenorhabditis elegans

## TL;DR

This study shows that the SAMS-1 gene is important for normal defecation in C. elegans, and its function is linked to phosphatidylcholine production.

## Contribution

The study identifies a novel role for SAMS-1 in regulating the defecation motor program and its connection to phosphatidylcholine levels.

## Key findings

- sams-1 mutants have longer defecation cycles compared to wild-type worms.
- Choline supplementation restores the Exp step in sams-1 mutants during aging.
- Phosphatidylcholine levels are linked to the regulation of the Exp step in sams-1 mutants.

## Abstract

Defecation is an ultradian rhythmic behavior in
Caenorhabditis elegans
. We investigated the involvement of
sams
family genes in regulating the defecation motor program. We found that

sams-1

mutants exhibited longer cycles than wild-type animals. With aging, the

sams-1

mutants also frequently skipped the expulsion (Exp) step of defecation behavior. The

sams-1

knockdown is known to reduce phosphatidylcholine (PC) levels, which are reversed by choline supplementation. We examined the effect of choline supplementation on defecation cycle times and Exp steps from adult days 1–4. Although choline supplementation did not alter the longer defecation cycle times of

sams-1

mutants, it restored the loss of the Exp step in

sams-1

mutants on adult days 3 and 4, suggesting a link between the regulation of the Exp step in

sams-1

mutants and PC production.