Purpose. We have cloned a new retina-specific gene named HRG4 using a differential cloning approach (Higashide et al., J. Biol. Chem., In press). Northern blot and in situ hybridization analyses revealed that its expression was highly retina-specific and was specifically localized in photoreceptors. Therefore, HRG4 may be a new candidate gene for retinal diseases and its gene structure and chromosomal localization are essential information for the screening of this gene for possible mutations. Methods. A human genomic Lambda Fix II library was screened with a full-length cDNA probe of HRG4. Several positive clones were analyzed by restriction enzyme digestion, Southern hybridization and DNA sequencing. The transcription initiation site was determined by primer extension and S1 nuclease protection assay. Southern hybridization with a human/rodent somatic cell hybrid mapping panel was performed for the chromosomal assignment of HRG4. Subchromosomal localization of HRG4 was determined by Southern hybridization with human/rodent somatic cell hybrids containing parts of chromosome 17. Results. HRG4 gene was composed of 5 exons and 4 introns and the entire gene region was contained in a 8 kb EcoRI fragment. A major transcription start site was located 68 bp upstream of the translation initiation site. The promoter region possessed multiple GC boxes and a PCE1-like sequence, but lacked any TATA boxes and CAAT boxes. Chromosomal mapping localized the HRG4 gene on chromosome 17q11.2. Conclusions. We have cloned, characterized and mapped the HRG4 gene. The gene structure and the chromosomal mapping of HRG4 are useful information for screening this gene as a candidate gene for retinal diseases.
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Feb 15 1996|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience