Function
Component of the cytoplasmic LSM1-LSM7 complex which is involved in mRNA degradation by promoting decapping and leading to accurate 5'-3' mRNA decay. LSM1A and LSM1B are essential for the formation of the cytoplasmic LSM1-LSM7 complex which regulates developmental gene expression by the decapping of specific development-related transcripts (PubMed:23221597, PubMed:23620288). Required for P-body formation during heat stress (PubMed:23221597).