Identification of BOIP, a novel cDNA highly expressed during spermatogenesis that encodes a protein interacting with the orange domain of the hairy-related transcription factor HRT1/Hey1 in Xenopus and mouse.
Hairy-related transcription factor (HRT/Hey) genes encode a novel subfamily of basic helix-loop-helix (bHLH) transcription factors related to the Drosophila hairy and Enhancer-of-split (E(spl)) and the mammalian HES proteins that function as downstream mediators of Notch signaling. Using the yeast two-hybrid approach, a previously uncharacterized protein was identified in Xenopus that interacts with XHRT1 (originally referred to as bc8), one member of the HRT/Hey subclass. This protein is evolutionarily conserved in chordates. It binds to sequences adjacent to the bHLH domain of XHRT1 known as the Orange domain and has been named bc8 Orange interacting protein (BOIP). BOIP shows a rather uniform subcellular localization and is recruited to the nucleus upon binding to XHRT1. In Xenopus, XBOIP mRNA is detected by RNase protection analysis throughout embryogenesis. In the adult, the strongest expression is detected in testis. In the mouse, high levels of BOIP mRNA are also found in adult testis. No expression is detected in the embryo and in any of the other adult organs tested. In situ hybridization revealed that BOIP transcripts were detected almost exclusively in round spermatids and that this expression overlaps with that of Hey1 (HRT1), which is expressed throughout spermatogenesis. In view of the importance of the Orange domain for HRT/Hey function, the newly identified BOIP proteins may serve as regulators specifically of HRT1/Hey1 activity.
Van Wayenbergh
Reginald
R
Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire (IRIBHM) and Institut de Biologie et de Médecine Moléculaires (IBMM), Université Libre de bruxelles, Gosselies, Belgium.
Taelman
Vincent
V
Pichon
Bruno
B
Fischer
Andreas
A
Kricha
Sadia
S
Gessler
Manfred
M
Christophe
Daniel
D
Bellefroid
Eric J
EJ
D000595:Amino Acid Sequence; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics*; D018797:Cell Cycle Proteins / Q000737:chemistry* / Q000378:metabolism; D003001:Cloning, Molecular; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000378:metabolism; D004625:Embryo, Nonmammalian; D018507:Gene Expression Regulation, Developmental; D015723:Gene Library; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008156:Luciferases / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051880:Receptors, Notch; D012260:Ribonucleases / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D013091:Spermatogenesis; D013094:Spermatozoa / Q000378:metabolism*; D013737:Testis / Q000378:metabolism; D014162:Transfection; D020798:Two-Hybrid System Techniques; D014981:Xenopus
D051792:Basic Helix-Loop-Helix Proteins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D018076:DNA, Complementary; D008156:Luciferases; D008565:Membrane Proteins; D009687:Nuclear Proteins; D012313:RNA; D012333:RNA, Messenger; D051880:Receptors, Notch; D012260:Ribonucleases; C485631:HEY1 protein, human; C120420:Hey1 protein, mouse