Rnf19a, a ubiquitin protein ligase, and Psmc3, a component of the 26S proteasome, tether to the acrosome membranes and the head-tail coupling apparatus during rat spermatid development.
We report the cDNA cloning of rat testis Rnf19a, a ubiquitin protein ligase, and show 98% and 93% protein sequence identity of testicular mouse and human Rnf19a, respectively. Rnf19a interacts with Psmc3, a protein component of the 19S regulatory cap of the 26S proteasome. During spermatid development, Rnf19a and Psmc3 are initially found in Golgi-derived proacrosomal vesicles. Later on, Rnf19a, Psmc3, and ubiquitin are seen along the cytosolic side of the acrosomal membranes and the acroplaxome, a cytoskeletal plate linking the acrosome to the spermatid nuclear envelope. Rnf19a and Psmc3 accumulate at the acroplaxome marginal ring-manchette perinuclear ring region during spermatid head shaping and in the developing sperm head-tail coupling apparatus and tail. Rnf19a and Psmc3 may interact directly or indirectly with each other, presumably pointing to the participation of the ubiquitin-proteasome system in acrosome biogenesis, spermatid head shaping, and development of the head-tail coupling apparatus and tail.
Rivkin
Eugene
E
Department of Cell Biology and Anatomy, The Sophie Davis School of Biomedical Education, New York, New York 10031, USA.
Kierszenbaum
Abraham L
AL
Gil
Mara
M
Tres
Laura L
LL
D000074183:ATPases Associated with Diverse Cellular Activities; D000177:Acrosome / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000378:metabolism / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D008969:Molecular Sequence Data; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism / Q000502:physiology*; D011485:Protein Binding; D051381:Rats; D017386:Sequence Homology, Amino Acid; D013077:Sperm Head / Q000378:metabolism / Q000502:physiology*; D013087:Spermatids / Q000378:metabolism / Q000502:physiology*; D013091:Spermatogenesis / Q000502:physiology; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
C543698:Rnf19a protein, rat; D044767:Ubiquitin-Protein Ligases; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease; D000251:Adenosine Triphosphatases; D000074183:ATPases Associated with Diverse Cellular Activities; C543699:Psmc3 protein, rat