Binds to the LIM domain of LIM domain-containing transcription factors (PubMed:10993673). Required for the blmp-1-mediated transcriptional activation or repression of several hypodermal genes, such as bed-3 (PubMed:32417234). Regulates sam-10 nuclear localization in PLM neurons (PubMed:21115607). Has a role in synaptic differentiation of PLM mechanosensory neurons (PubMed:21115607). Involved in gonadogenesis (PubMed:12736204). Interacts with blmp-1. Expressed in all neurons and some other tissues of the adult, including vulval muscle, and, in males, all the neurons of the tail region (PubMed:10993673). Expressed in vulval cells (PubMed:12736204, PubMed:10993673). First expressed widely in 200- to 260-minute-old embryo, except in hyp-7 cells (PubMed:10993673). Expression becomes more restricted to the anterior, ventral, and posterior part in the comma stage embryo (PubMed:10993673). Expressed in all neurons and some other tissues of the larva (PubMed:10993673). Expressed in primary vulval cells during the L4 larval stage (PubMed:12736204). RNAi-mediated knockdown causes mechanosensory defects and uncoordination in L1 and L2 larval stage animals; phenotypes become weaker in later stages and eventually disappear in young adults (PubMed:10993673). RNAi-mediated knockdown causes defects in vulval morphology and gonad arms (PubMed:12736204). RNAi-mediated knockdown reduces the level of bed-3 and col-124 mRNAs and increases the level of lin-29 mRNA (PubMed:32417234). Belongs to the LDB family. Extended N-terminus.