| Primary Identifier | Expr9851 | Subcellular Localization | After nuclear envelope breakdown (NEBD), the two condensin complexes occupied distinct domains. Condensin I was found at the interface between homologs marked by reduced DAPI staining ("DAPI-free zone"), whereas condensin II localizes to sister chromatids throughout meiosis. During anaphase, condensin I localized on the acentrosomal meiotic spindle between separating chromosomes. As in mitosis, condensin I colocalized with AIR-2 on chromosomes during prometaphase and metaphase of meiosis, and on the spindle during anaphase. Condensin I localizes to the short arms of bivalents, where cohesion between the exchanged parts of sister chromatids holds homologs together. Condensin localization in the male germline followed the same general pattern. Both condensins I and II began to accumulate in nuclei by late pachytene. Condensin II associated with chromosomes before NEBD, but condensin I chromosomal enrichment was not seen until after NEBD in late diakinesis. Following NEBD, condensin I was between aligned homologs (meiosis I) and between sisters (meiosis II), whereas condensin II remained associated with sister chromatids throughout. Interestingly, condensin I behavior in sperm and oocytes differed at anaphase. In oocytes, condensin I colocalized with microtubules and AIR-2 between separating chromosomes during anaphase. In sperm, AIR-2 and microtubules were not prominent between separating chromosomes, and condensin I was absent from this region. Instead, condensin I and AIR-2 colocalized on the inner edges of separating chromosomes. In early prophase, only condensin II associated with chromosomes. Condensin I loaded onto chromosomes after nuclear pore complexes disassembly in prometaphase. From prometaphase to anaphase, the spatial patterns of condensins I and II were different, with condensin II in a centromere-like pattern and condensin I diffusely coating all chromosomes. During anaphase, condensin I was also seen colocalizing with microtubules at the spindle midzone in addition to the chromosomal signal. The other condensin I CAP subunits, DPY-26 and DPY-28, associated with chromosomes at the same time and with similar patterns to that of CAPG-1. Furthermore, the chromosomal association of CAPG-1 was dependent on the presence of DPY-26 and DPY-28, indicating that the condensin I CAP subunits associate with mitotic chromosomes as a complex. |
| WormBase Gene ID | Gene Name | Sequence Name | Organism |
|---|---|---|---|
| WBGene00001085 | dpy-26 | C25G4.5 | Caenorhabditis elegans |
| WBGene00001087 | dpy-28 | Y39A1B.3 | Caenorhabditis elegans |
| WBGene00001833 | hcp-6 | Y110A7A.1 | Caenorhabditis elegans |
| WBGene00009254 | capg-1 | F29D11.2 | Caenorhabditis elegans |
