Nulp1, a novel basic helix-loop-helix protein expressed broadly during early embryonic organogenesis and prominently in developing dorsal root ganglia.
The basic helix-loop-helix (bHLH) proteins control differentiation and development of a variety of organs. We have isolated the complementary DNA (cDNA) of a novel class of bHLH transcription factors. The previously uncharacterized bHLH messenger RNA (mRNA) was identified by RNA fingerprinting by comparing embryonic and adult mRNA. The reading frame sequence predicts a new class of bHLH family. Northern blotting of embryonic stages demonstrated a 3.2-kb transcript present in several embryonic tissues, including kidney, brain, heart, and lung, in a fashion confirmatory with the RNA-fingerprinting data. In situ hybridization of cryosections detected strong signals in the dorsal root ganglia of 14-day-old mouse embryos (E14). Transient transfection of human embryonic kidney cells with Nulp1-EGFP demonstrated nuclear localization. The complex expression pattern and unique protein sequence, including an acidic amino terminal and putative transcription activation domain, suggests that Nulp1 may have a distinct role in embryonic development of many organs, including the adult brain.
Olsson
Magnus
M
Department of Cell and Molecular Biology, Section for Cell and Developmental Biology, Lund University, BMC, B12, Sölvegatan 19, 221 84 Lund, Sweden.
Durbeej
Madeleine
M
Ekblom
Peter
P
Hjalt
Tord
T
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins; D015152:Blotting, Northern; D002467:Cell Nucleus / Q000235:genetics; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005727:Ganglia, Spinal / Q000196:embryology* / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D019077:Helix-Turn-Helix Motifs / Q000235:genetics*; D017403:In Situ Hybridization; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis; D014157:Transcription Factors / Q000235:genetics*
D051792:Basic Helix-Loop-Helix Proteins; D018076:DNA, Complementary; D012333:RNA, Messenger; D014157:Transcription Factors; C470487:Nulp1 protein, mouse