title: The transcription factor chicken Scratch2 is expressed in a subset of early postmitotic neural progenitors.
abstract: Scratch proteins are members of the Snail superfamily which have been shown to regulate invertebrate neural development. However, in vertebrates, little is known about the function of Scratch or its relationship to other neural transcription factors. We report the cloning of chicken Scratch2 (cScrt2) and describe its expression pattern in the chick embryo from HH15 through HH29. cScrt2 was detected in cranial ganglia, the nasal placode and neural tube. At all stages examined, cScrt2 expression is only detected within a subregion of the intermediate zone of the neural tube. cScrt2 is also expressed in the developing dorsal root ganglia from HH22-23 onwards and becomes limited to its dorsal medial domain at HH29. phospho-Histone H3 and BrdU-labeling revealed that the cScrt2 expression domain is located immediately external to the proliferative region. In contrast, cScrt2 domain overlapped almost completely with that of the postmitotic neural transcription factor NeuroM/Ath3/NEUROD4. Together, these data define cScrt2-positive cells as a subset of immediately postmitotic neural progenitors. Previous data has shown that Scrt2 is a repressor of E-box-driven transcription whereas NeuroM is an E-box-transactivator. In light of these data, the co-localization detected here suggests that Scrt2 and NeuroM may have opposing roles during definition of neural subtypes.
authors.affiliation: Department of Cell and Developmental Biology, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Felipe Monteleone
authors.initials: FM
authors.lastname: Vieceli
authors.forename: Marcos
authors.initials: M
authors.lastname: Simões-Costa
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Turri
authors.forename: Tatiane
authors.initials: T
authors.lastname: Kanno
authors.forename: Marianne
authors.initials: M
authors.lastname: Bronner
authors.forename: Chao Yun Irene
authors.initials: CY
authors.lastname: Yan
mesh_terms: D000818:Animals; D030161:Avian Proteins / Q000096:biosynthesis*; D051792:Basic Helix-Loop-Helix Proteins / Q000096:biosynthesis*; D002645:Chickens / Q000235:genetics / Q000254:growth & development*; D005727:Ganglia, Spinal / Q000254:growth & development* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D009432:Neural Crest / Q000254:growth & development; D054259:Neural Tube / Q000254:growth & development / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D009479:Neuropeptides / Q000096:biosynthesis*; D014157:Transcription Factors / Q000096:biosynthesis* / Q000235:genetics*
chemical_list: D030161:Avian Proteins; D051792:Basic Helix-Loop-Helix Proteins; D009479:Neuropeptides; D014157:Transcription Factors; C108527:NeuroM protein, chicken