# Impact of embryo size on apoptosis in C. elegans

## TL;DR

This study shows that smaller cells in C. elegans embryos are more likely to undergo programmed cell death.

## Contribution

The study demonstrates that cell size directly influences apoptosis in genetically manipulated C. elegans embryos.

## Key findings

- Knock-down of C27D9.1 increases inappropriate cell survival in apoptosis-compromised embryos.
- Reducing embryo size via ima-3 RNAi partially suppresses inappropriate cell survival.
- Smaller cells are more likely to undergo apoptosis in C. elegans embryos.

## Abstract

During

C. elegans

development 131 somatic cells reproducibly undergo programmed cell death. Many of these 131 cells ‘programmed to die' are the smaller daughter of a neuroblast that divides asymmetrically and die through apoptosis. To determine whether cell size impacts the ability of cells programmed to die to undergo apoptosis, we increased or decreased embryo size by RNA interference-mediated knock-down of the genes

C27D9.1

or

ima-3

, respectively. We found that in apoptosis-compromised genetic backgrounds,

C27D9.1

(
RNAi
) enhances and

ima-3

(
RNAi
) partially suppresses inappropriate survival of cells programmed to die. This supports the notion that in

C. elegans

embryos, an increase in cell size compromises and a decrease in cell size promotes the ability of cells programmed to die to undergo apoptosis.