Structural Maintenance Of Chromosomes Protein 2 (SMC2)

Members of the SMC, family are critical for mitotic chromosome condensation in frogs and for DNA repair in mammals.Sequence analysis predicted that the 1,197-amino acid CAPE protein is 80% identical to the Xenopus sequence. Northern blot analysis detected a 4.5-kb transcript. Western blot and immunoprecipitation analyses showed that CAPE is expressed as a 135-kD soluble nuclear protein throughout the cell cycle in a variety of cell lines and is associated with CAPC in a heterodimeric complex. Immunofluorescence analysis demonstrated that the proteins are associated with condensed chromosomes in mitotic cells and show dense speckles in interphase nuclei. Microinjection of anti-CAPC or anti-CAPE failed to arrest mitosis in metaphase cells, in contrast to antibody to SMC1L1.