Proteolytic cleavage of ALF into alpha- and beta-subunits that form homologous and heterologous complexes with somatic TFIIA and TRF2 in male germ cells.
Male germ cells specifically express paralogues of components of the general transcription apparatus including ALF a paralogue of TFIIAalpha/beta. We show that endogenous ALF is proteolytically cleaved to give alpha- and beta-subunits and we map the proteolytic cleavage site by mass spectrometry. Immunoprecipitations show that ALFalpha- and beta-subunits form a series of homologous and heterologous complexes with somatic TFIIA which is coexpressed in male germ cells. In addition, we show that ALF is coexpressed in late pachytene spermatocytes and in haploid round spermatids with transcription factor TRF2, and that these proteins form stable complexes in testis extracts. Our observations highlight how cleavage of ALF and coexpression with TFIIA and TRF2 increases the combinatorial possibilities for gene regulation at different developmental stages of spermatogenesis.
Catena
Raffaella
R
Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch Cédex, France.
Argentini
Manuela
M
Martianov
Igor
I
Parello
Catherine
C
Brancorsini
Stefano
S
Parvinen
Martti
M
Sassone-Corsi
Paolo
P
Davidson
Irwin
I
D000595:Amino Acid Sequence; D000818:Animals; D002457:Cell Extracts / Q000276:immunology; D017124:Conserved Sequence; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D021122:Protein Subunits / Q000032:analysis / Q000378:metabolism; D013090:Spermatocytes / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D013091:Spermatogenesis / Q000235:genetics; D035341:Telomeric Repeat Binding Protein 2 / Q000032:analysis / Q000378:metabolism*; D013737:Testis / Q000166:cytology; D035561:Transcription Factor TFIIA / Q000032:analysis / Q000378:metabolism*; D014157:Transcription Factors / Q000032:analysis / Q000378:metabolism*
D002457:Cell Extracts; C485619:Gtf2a1lf protein, mouse; D021122:Protein Subunits; D035341:Telomeric Repeat Binding Protein 2; D035561:Transcription Factor TFIIA; D014157:Transcription Factors