Structural maintenance of chromosomes protein 4 (SMC4)

Structural maintenance of chromosomes protein 4 (SMC4) is a core subunit of the condensin complex—specifically condensin I and II—involved in higher-order chromosome organization, condensation, and segregation during mitosis and meiosis[1][2][3]. SMC4 belongs to the SMC gene family of chromosomal ATPases, characterized by highly conserved nucleotide-binding motifs and complex dimerization[1][2][3]. It pairs with SMC2 to form a heterodimeric V-shaped structure central to condensin holocomplex function, which also includes three additional non-SMC subunits[1]. SMC4 plays critical roles in mitotic chromosome condensation and segregation, maintenance of chromosome structure, DNA repair, and silenced gene expression[3]. SMC4 is essential during development, and its abnormal expression is linked to several cancers—its overexpression promotes tumor cell proliferation and invasion, and is associated with poor prognosis in lung adenocarcinoma and other malignancies[3].

Other names

Chromosome-associated polypeptide CCAP-CXCAP-C homologSMC protein 4SMC4L1hCAP-C