Essential protein required for both chromosome condensation and segregation and X-chromosome dosage compensation depending on its binding partners (PubMed:9458050, PubMed:11914278, PubMed:19119011, PubMed:18198337, PubMed:19781752). Central component of the condensin I complex, a complex required for conversion of interphase chromatin into mitotic-like condense chromosomes (PubMed:11914278, PubMed:18198337, PubMed:19119011). The condensin complex introduces positive supercoils into relaxed DNA in the presence of type I topoisomerases (PubMed:11914278). Converts nicked DNA into positive knotted forms in the presence of type II topoisomerases (By similarity). Central component of the condensin II complex, a complex that seems to play a role in prophase chromosome condensation and organization (PubMed:19119011, PubMed:15557118). Both the condensin complex I and II play a role in meiotic and mitotic chromosome segregation (PubMed:11914278, PubMed:19119011, PubMed:15557118). Plays a role in robust cytokinesis upon the presence of chromatin obstructions (PubMed:23684975). Also a member of the condensin I-like dosage compensation complex that associates specifically with hermaphrodite X chromosomes to reduce their gene transcription during interphase (PubMed:9458050, PubMed:19119011, PubMed:18198337, PubMed:19781752). Component of the condensin I complex, which contains the mix-1/SMC2 and smc-4/SMC4 heterodimer, and three non SMC subunits that probably regulate the complex: dpy-26, capg-1 and dpy-28 (PubMed:11914278, PubMed:19119011, PubMed:19781752, PubMed:18198337). Within the complex, interacts with smc-4, dpy-26, dpy-28 and capg-1 (PubMed:11914278, PubMed:15557118, PubMed:19781752, PubMed:19119011, PubMed:28301465). Interaction with smc-4 is required for mitotic chromosome localization (PubMed:11914278). Component of the condensin II complex, which contains the mix-1/SMC2 and smc-4/SMC4 heterodimer, and three non SMC subunits, capg-2, kle-2 and hcp-6 that probably regulate the complex (PubMed:19119011, PubMed:15557118). Within the complex, interacts with smc-4, capg-2, kle-2 and hcp-6 (PubMed:11914278, PubMed:15557118, PubMed:19119011, PubMed:28301465). Also a component of the condensin-like dosage compensation complex, which contains the mix-1/SMC2 and dpy-27/SMC4 heterodimer, and three non SMC subunits that probably regulate the complex: dpy-26, capg-1 and dpy-28 (PubMed:11914278, PubMed:19119011, PubMed:18198337, PubMed:19781752, PubMed:15557118). Within the complex, interacts with dpy-27, dpy-26, capg-1 and dpy-28 (PubMed:11914278, PubMed:15557118, PubMed:18198337, PubMed:19781752, PubMed:19119011, PubMed:28301465). Requires capg-1 for hermaphrodite X chromosome localization (PubMed:19119011). Interacts with smcl-1 (PubMed:28301465). During mitosis and meiosis, localizes to condensed chromosomes in both sexes (PubMed:11914278, PubMed:19119011, PubMed:15557118). During meiotic prophase, surrounds the chromosomes, localizes between homologs during meiotic metaphase I, and localizes between sister chromatids during metaphase II (PubMed:11914278). During mitotic metaphase, localizes at the poleward face and to the core of the condensed chromosomes (PubMed:19119011, PubMed:18198337, PubMed:15557118). Requires hcp-6 for the localization to meiotic chromosomes (PubMed:15557118). After the 40-cell stage when dosage compensation is initiated, specifically localizes to the hermaphrodite X chromosomes in interphase (PubMed:9458050, PubMed:11914278). Expressed in embryos and in adult somatic and germline tissues (at protein level). The flexible SMC hinge domain, which separates the large intramolecular coiled coil regions, allows the heterodimerization with SMC4, forming a V-shaped heterodimer. RNAi-mediated knockdown disrupts mitotic prophase chromosome condensation and chromosome segregation in anaphase leading to aneuploidy (PubMed:11914278, PubMed:19119011). Results in cleavage furrow regression and failed cytokinesis during the second embryonic division (PubMed:23684975). Belongs to the SMC family. SMC2 subfamily.