Cloning, gene expression, and characterization of CP27, a novel gene in mouse embryogenesis

We report the full-length sequencing, tissue-specific expression, and immun olocalization of cp27, a novel gene in mouse embryogenesis. The cp27 gene w as isolated and cloned from a mouse E11 lambda gt11 library using a peptide antibody that recognized a distinct expression pattern in mouse craniofaci al development. The cp27 gene contains an open reading frame of 295 amino a cids corresponding to a predicted molecular mass of 33 kDa. On Western blot s, a polyclonal antibody against CP27 detected a single epitope at 27 kDa. The putative CP27 protein has an isoelectric point of 4.75 and features a d istinct helix-loop-helix structure according to prediction algorithms. We h ave cloned the human cp27 gene and mapped it to a locus on the human chromo some 16 which is in proximity to several loci associated with inherited cra niofacial diseases such as fanconi anemia type A. Northern blot analysis of RNA from multiple mouse tissues demonstrated high levels of expression in developing mouse teeth, heart, lung, and liver of a single transcript of ap prox. 1.8 kbp. In situ hybridization using a radioactive RNA probe resulted in distinct signals in the developing neuroepithelium, cerebellum, heart, lung, liver, teeth, salivary glands, and periosteum of developing bones. Im munohistochemical staining of developing mouse tissues detected epitopes sp ecific for CP27 in the mesenchyme surrounding the primary brain vesicles, i n basement membranes, in the periosteum, in salivary glands, and in the ste llate reticulum of teeth. Thus, CP27 represents a unique gene product invol ved in mouse embryogenesis. (C) 1999 Elsevier Science B.V. All rights reser ved.