Ssdp proteins interact with the LIM-domain-binding protein Ldb1 to regulate development.
The LIM-domain-binding protein Ldb1 is a key factor in the assembly of transcriptional complexes involving LIM-homeodomain proteins and other transcription factors that regulate animal development. We identified Ssdp proteins (previously described as sequence-specific, single-stranded-DNA-binding proteins) as components of Ldb1-associated nuclear complexes in HeLa cells. Ssdp proteins are associated with Ldb1 in a variety of additional mammalian cell types. This association is specific, does not depend on the presence of nucleic acids, and is functionally significant. Genes encoding Ssdp proteins are well conserved in evolution from Drosophila to humans. Whereas the vertebrate Ssdp gene family has several closely related members, the Drosophila Ssdp gene is unique. In Xenopus, Ssdp encoded by Drosophila Ssdp or mouse Ssdp1 mRNA enhances axis induction by Ldb1 in conjunction with the LIM-homeobox gene Xlim1. Furthermore, we were able to demonstrate an interaction between Ssdp and Chip (the fly homolog of Ldb1) in Drosophila wing development. These findings indicate functional conservation of Ssdp as a cofactor of Ldb1 during invertebrate and vertebrate development.
Chen
Lan
L
Laboratory of Mammalian Genes and Development, and Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20814, USA.
Segal
Daniel
D
Hukriede
Neil A
NA
Podtelejnikov
Alexandre V
AV
Bayarsaihan
Dashzeveg
D
Kennison
James A
JA
Ogryzko
Vasily V
VV
Dawid
Igor B
IB
Westphal
Heiner
H
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D060588:LIM Domain Proteins; D060850:LIM-Homeodomain Proteins; D051379:Mice; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases; D014709:Vero Cells; D014981:Xenopus / Q000196:embryology; D029867:Xenopus Proteins; D060589:Zyxin
C108740:Chi protein, Drosophila; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; C486312:LDB1 protein, human; C085473:LHX1 protein, human; D060588:LIM Domain Proteins; D060850:LIM-Homeodomain Proteins; C102084:Ldb1 protein, mouse; C543964:Lhx1 protein, Xenopus; C499523:Lhx1 protein, mouse; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins; C504091:NABP2 protein, human; C504094:SSBP3 protein, human; C504092:Ssbp2 protein, mouse; C504093:Ssbp3 protein, mouse; C520429:Ssdp protein, Drosophila; D014157:Transcription Factors; C486314:XLdb1 protein, Xenopus; D029867:Xenopus Proteins; C499520:Zyx protein, Drosophila; D060589:Zyxin; C467728:STUB1 protein, human; D044767:Ubiquitin-Protein Ligases