Loss of CABLES1, a cyclin-dependent kinase-interacting protein that inhibits cell cycle progression, results in germline expansion at the expense of oocyte quality in adult female mice.
Recent studies have shown that cell cycle inhibitors encoded by the Ink4a gene locus constrain the self-renewing activity of adult stem cells of the hematopoietic and nervous systems. Here we report that knockout (KO) of the Cables1 [cyclin-dependent kinase (CDK)-5 and ABL enzyme substrate 1] cell cycle-regulatory gene in mice has minimal to no effect on hematopoietic stem cell (HSC) dynamics. However, female Cables1-null mice exhibit a significant expansion of germ cell (oocyte) numbers throughout adulthood. This is accompanied by a dramatic elevation in the number of atretic immature oocytes within the ovaries and an increase in the incidence of degenerating oocytes retrieved following superovulation of CABLES1-deficient females. These outcomes are not observed in mice lacking p16INK4a alone or both p16INK4a and p19ARF. These data support recent reports that adult female mice can generate new oocytes and follicles but the enhancement of postnatal oogenesis by Cables1 KO appears offset by a reduction in oocyte quality, as reflected by increased elimination of these additional germ cells via apoptosis. This work also reveals cell lineage specificity with respect to the role that specific CDK-interacting proteins play in restraining the activity of adult germline versus somatic stem cells.
Lee
Ho-Joon
HJ
Vincent Center for Reproductive Biology, Vincent Obstetrics and Gynecology Service, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts 02114, USA.
Sakamoto
Hideo
H
Luo
Hongwei
H
Skaznik-Wikiel
Malgorzata E
ME
Friel
Anne M
AM
Niikura
Teruko
T
Tilly
Jacqueline C
JC
Niikura
Yuichi
Y
Klein
Rachael
R
Styer
Aaron K
AK
Zukerberg
Lawrence R
LR
Tilly
Jonathan L
JL
Rueda
Bo R
BR
D000367:Age Factors; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D002452:Cell Count; D002453:Cell Cycle / Q000502:physiology*; D018844:Cyclin-Dependent Kinases / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D016213:Cyclins / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D005260:Female; D005854:Germ Cells / Q000166:cytology / Q000254:growth & development; D006131:Growth Inhibitors / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009865:Oocytes / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D010063:Ovum / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D010750:Phosphoproteins / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism* / Q000502:physiology
C411580:Cables1 protein, mouse; D002352:Carrier Proteins; D016213:Cyclins; D006131:Growth Inhibitors; D010750:Phosphoproteins; D018844:Cyclin-Dependent Kinases