Regulatory subunit of the condensin-2 complex, a complex which establishes mitotic chromosome architecture and is involved in physical rigidity of the chromatid axis (By similarity). Plays a role in the embryonic development of the head and kidney structures (PubMed:30609410). Component of the condensin-2 complex, which contains the smc2 and smc4 heterodimer, and three non SMC subunits that probably regulate the complex: ncaph2, ncapd3 and ncapg2. At 3 dpf, mutant animals exhibit cerebellar hypoplasia, a reduction in the anterior structures, including the optic tecta, and an increase in cell proliferation in the head (PubMed:30609410). At 2 dpf, aberrant mitotic cell-cycle progression and an increase in cell death (PubMed:30609410). At 4 dpf, renal defects including renal aplasia, hypoplasia and enlargment of the proximal renal convolution tubule are observed (PubMed:30609410). Morpholino knockdown results in reduced head size, increased cell proliferation in the head, increased cell death and increased renal-tubule diameter (PubMed:30609410). In a double morpholino knockdown together with nphp1, the increase in renal-tubule diameter is exacerbated (PubMed:30609410).