SHARPs: mammalian enhancer-of-split- and hairy-related proteins coupled to neuronal stimulation.
In the mammalian central nervous system, a diverse group of basic helix-loop-helix (bHLH) proteins is involved in the determination of progenitor cells and, subsequently, in regulating neuronal differentiation. Here we report the identification of a novel subfamily of bHLH proteins, defined by two mammalian enhancer-of-split- and hairy-related proteins, termed SHARP-1 and SHARP-2. In contrast to known bHLH genes, detectable transcription of SHARP genes begins at the end of embryonic development marking differentiated neurons that have reached a final position, and increases as postnatal development proceeds. In the adult, SHARP genes are expressed in subregions of the CNS that have been associated with adult plasticity. In PC12 cells, a model system to study neurite outgrowth, SHARP genes can be induced by NGF with the kinetics of an immediate-early gene. Similarly, within 1 h after the administration of kainic acid in vivo, SHARP-2 is induced in neurons throughout the rat cerebral cortex. This suggests that neuronal bHLH proteins are also involved in the "adaptive" changes of mature CNS neurons which are coupled to glutamatergic stimulation.
Rossner
M J
MJ
Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Germany.
Dörr
J
J
Gass
P
P
Schwab
M H
MH
Nave
K A
KA
D000595:Amino Acid Sequence; D000818:Animals; D000831:Animals, Newborn; D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins / Q000502:physiology; D029721:Drosophila Proteins; D004622:Embryo, Mammalian; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018257:Helix-Loop-Helix Motifs / Q000235:genetics / Q000502:physiology*; D018398:Homeodomain Proteins; D019476:Insect Proteins / Q000502:physiology; D007608:Kainic Acid / Q000494:pharmacology; D008297:Male; D008969:Molecular Sequence Data; D005810:Multigene Family; D009414:Nerve Growth Factors / Q000494:pharmacology; D009474:Neurons / Q000502:physiology*; D009479:Neuropeptides / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D016716:PC12 Cells; D051381:Rats; D017207:Rats, Sprague-Dawley; D012097:Repressor Proteins / Q000502:physiology; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D019476:Insect Proteins; D007608:Kainic Acid; D009414:Nerve Growth Factors; D009479:Neuropeptides; D012097:Repressor Proteins; D014157:Transcription Factors; C491538:Bhlhe40 protein, rat; C109509:Bhlhe41 protein, rat; C084530:E(spl)mdelta-HLH protein, Drosophila; C061841:hairy protein, insect