Transplantation of somatic nuclei into oocyte cytoplasm reveals that the chromosome properties determine the chromosome separation fate in rabbit.
G2/M somatic nuclei were introduced into enucleated meiotically competent oocytes and subsequently cultured in TCM199 plus 10% fetal calf serum (FCS). Pseudo-first polar bodies could be extruded, but the chromosomes failed to arrange normally. Kinetochores were traced with immunofluorescent microscopy using autoimmune sera from patients with CREST (Calcinosis, Raynaud's phenomenon, Esophageal dysmotility, Sclerodactyly, Telangiectasia) scleroderma. In vitro matured oocytes arrested at second meiotic metaphase and kinetochores were detectable as paired structures aligned at the spindle equator. At meiotic anaphase, present or past the kinetochores separated and remained aligned at the distal sides of the chromosomes until telophase, when their alignment perpendicular to the spindle axis was lost. Kinetochores failed to arrange normally after transferring somatic nuclei into oocytes. Our results suggest that somatic cell nuclei are unable to proceed normally through meiosis when introduced into oocyte meiotic cytoplasm.
Zhang
Li-sheng
LS
State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, People's Republic of China.
Yao
Li-Juan
LJ
Jiang
Yan
Y
Jiang
Man-Xi
MX
Lei
Zi-Li
ZL
Sun
Qing-Yuan
QY
Chen
Da-Yuan
DY
D000818:Animals; D002460:Cell Line; D020090:Chromosome Segregation / Q000502:physiology*; D033481:Chromosomes, Mammalian / Q000235:genetics / Q000502:physiology*; D003593:Cytoplasm / Q000502:physiology*; D007150:Immunohistochemistry / Q000662:veterinary; D018386:Kinetochores / Q000378:metabolism*; D008540:Meiosis / Q000502:physiology*; D008856:Microscopy, Fluorescence / Q000662:veterinary; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D011817:Rabbits