Haploinsufficiency at the protein kinase A RI alpha gene locus leads to fertility defects in male mice and men.
Carney complex (CNC) is a familial multiple neoplasia syndrome characterized by spotty skin pigmentation, cardiac and cutaneous myxomas, and endocrine tumors. CNC is inherited as an autosomal dominant trait and is transmitted with greater frequency by women vs. men. Nearly two thirds of CNC patients are heterozygous for inactivating mutations in the gene encoding the protein kinase A (PKA) type I alpha regulatory subunit (RI alpha), PRKAR1. We report here that male mice heterozygous for the Prkar1a gene have severely reduced fertility. Sperm from Prkar1a heterozygous mice are morphologically abnormal and reduced in number. Genetic rescue experiments reveal that this phenotype results from elevated PKA catalytic activity in germ cells as early as the pachytene stage of spermatogenesis. Consistent with this defect in the male mutant mice, sperm from CNC patients heterozygous for PRKAR1A mutations were also found to be morphologically aberrant and decreased in number. We conclude that unregulated PKA activity in male meiotic or postmeiotic germ cells leads to structural defects in mature sperm and results in reduced fertility in mice and humans, contributing to the strikingly reduced transmission of PRKAR1A inactivating mutations by male patients with CNC.
Burton
Kimberly A
KA
Department of Pharmacology, University of Washington School of Medicine, Box 357750, Seattle, Washington 98195-7750, USA.
McDermott
Deborah A
DA
Wilkes
David
D
Poulsen
Melissa N
MN
Nolan
Michael A
MA
Goldstein
Marc
M
Basson
Craig T
CT
McKnight
G Stanley
GS
D000818:Animals; D015153:Blotting, Western; D054756:Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007248:Infertility, Male / Q000209:etiology / Q000235:genetics*; D040582:Inheritance Patterns; D008297:Male; D051379:Mice; D008854:Microscopy, Electron; D009377:Multiple Endocrine Neoplasia / Q000150:complications / Q000235:genetics*; D013094:Spermatozoa / Q000473:pathology* / Q000502:physiology / Q000648:ultrastructure
D054756:Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; C517834:PRKAR1A protein, human; C517835:Prkar1a protein, mouse; D017868:Cyclic AMP-Dependent Protein Kinases