TY - JOUR
T1 - Breakdown of cytoskeletal proteins during meiosis of starfish oocytes and proteolysis induced by calpain
AU - Santella, Luigia
AU - Kyozuka, Keiichiro
AU - Hoving, Sjouke
AU - Munchbach, Martin
AU - Quadroni, Manfredo
AU - Dainese, Paola
AU - Zamparelli, Carlotta
AU - James, Peter
AU - Carafoli, Ernesto
PY - 2000/8/25
Y1 - 2000/8/25
N2 - Meiosis reinitiation in starfish oocytes is characterized by Ca2+ transients in the cytosol and in the nucleus and is accompanied by the disassembly of the nuclear envelope, a process which is likely to be mediated by the cleavage of selected proteins. We have used mass spectrometry analysis (mass profile fingerprinting) on 2D polyacrylamide gels of extracts of oocytes in which meiosis resumption was induced by 1-methyladenine and have identified five proteins that were specifically degraded: α-tubulin, lamin B, dynamin, and two kinds of actin. They are all components of the cytoskeleton or associated with it. We then investigated whether calpain, which is activated by the increase in cell Ca2+, could cleave the same proteins that became degraded under the influence of 1-methyladenine and thus be involved in nuclear membrane breakdown. The investigation was prompted by the finding that microinjection of calpain into the nuclei of prophase arrested oocytes induced meiosis in the absence of 1-methyladenine. Incubation of prophase arrested (disrupted) oocytes with calpain produced a 2D gel protein pattern in which some of the degradation products coincided with those seen in oocytes challenged with 1-methyladenine. (C) 2000 Academic Press.
AB - Meiosis reinitiation in starfish oocytes is characterized by Ca2+ transients in the cytosol and in the nucleus and is accompanied by the disassembly of the nuclear envelope, a process which is likely to be mediated by the cleavage of selected proteins. We have used mass spectrometry analysis (mass profile fingerprinting) on 2D polyacrylamide gels of extracts of oocytes in which meiosis resumption was induced by 1-methyladenine and have identified five proteins that were specifically degraded: α-tubulin, lamin B, dynamin, and two kinds of actin. They are all components of the cytoskeleton or associated with it. We then investigated whether calpain, which is activated by the increase in cell Ca2+, could cleave the same proteins that became degraded under the influence of 1-methyladenine and thus be involved in nuclear membrane breakdown. The investigation was prompted by the finding that microinjection of calpain into the nuclei of prophase arrested oocytes induced meiosis in the absence of 1-methyladenine. Incubation of prophase arrested (disrupted) oocytes with calpain produced a 2D gel protein pattern in which some of the degradation products coincided with those seen in oocytes challenged with 1-methyladenine. (C) 2000 Academic Press.
KW - Calcium
KW - Calpain
KW - Nuclear envelope
KW - Oocyte maturation
KW - Proteolysis
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U2 - 10.1006/excr.2000.4969
DO - 10.1006/excr.2000.4969
M3 - Article
C2 - 10942584
AN - SCOPUS:0034714442
VL - 259
SP - 117
EP - 126
JO - Experimental Cell Research
JF - Experimental Cell Research
SN - 0014-4827
IS - 1
ER -