Revisiting the Small Heat Shock Protein Family in Caenorhabditis elegans: Insights from Phylogenetic, Structural, and Functional Analyses.

Small heat shock proteins (sHSPs) are ATP-independent molecular chaperones with diverse cellular functions. Here, we systematically reassessed two subfamilies of sHSPs in C. elegans by integrating evolutionary, genomic, and biophysical analyses. We report analysis of 18 α-crystallin domain-containing sHSPs, including two previously uncharacterized HSP-16-like proteins (designated hsp-16.31 & hsp-16.32 ). This analysis also supports the inclusion of two other proteins, ZK1128.7 and Y55F3BR.6 , as additional members of the C. elegans sHSP family. Comparative analyses reveal substantial diversity in tissue expression, intrinsic disorder, and liquid-liquid phase separation (LLPS) propensity, highlighting extensive functional specialization within the family.