Lamins are components of the nuclear lamina, a fibrous layer on the nucleoplasmic side of the inner nuclear membrane, which is thought to provide a framework for the nuclear envelope and may also interact with chromatin (By similarity). In spermatocytes, regulates cytokinesis during meiosis (PubMed:27402967). Interacts with MAN1. Nuclear periphery (PubMed:7593280). In premeiotic nuclei of primary spermatocytes, localization to the nuclear lamina depends on type-B lamin Lam. In spermatocytes, temporarily depleted between anaphase I and telophase I, and anaphase II and telophase II. First detected from late stage 12 in the oenocytes, abdominal segments, hindgut and posterior spiracles, with expression increasing in stage 13 (PubMed:7593280) (at protein level). In stage 14, also becomes detectable in the foregut (PubMed:7593280) (at protein level). Stage 15 shows expression in the epidermis, dorsal longitudinal trunk, pharynx, esophagus and proventriculus, with the dorsal pharyngeal musculature showing expression in late stage 15 (PubMed:7593280) (at protein level). In stage 16 embryos, also detected in the exit glia with increasing expression in the somatic musculature (PubMed:7593280) (at protein level). Also detected in the visceral mesoderm but not in the midgut or central nervous system until the end of embryogenesis (PubMed:7593280) (at protein level). In third instar larvae, detectable at varying levels in all cell types (PubMed:7593280) (at protein level). Expressed in spermatocytes (at protein level) (PubMed:27402967). Expressed in 12-22 hours embryos. Expression peaks in larvae and declines in pupae and adults. Belongs to the intermediate filament family.