Radiation Hybrid Mapping and mRNA Expression of Chicken N-downregulated gene 4

摘要

N-myc downregulated gene 4 (NDRG4) is a member of the N-myc downregulated gene family which belongs to the alpha/beta hydrolase superfamily. The protein encoded by this gene is a cytoplasmic protein that may be involved in the regulation of mitogenicsignalling in vascular smooth muscle cells. To map NDRG4 gene in chicken chromosome, a 6,000 rads chicken-hamster radiation hybrid panel was used. Primers were designed according to the published human sequence for amplification of chicken NDRG4. We compared the corresponding human mRNA sequence with the predicted coding sequence of chicken NDRG4, and found that the assembled contig shared a high percentage of similarity with that of human gene. PCR of samples from ChickRH6 revealed the locations of NDRG4 to be linked to the maker PARD6G (5 cR away) with a LOD score 20.46. In addition, we detected the mRNA expression and distribution of chicken NDRG4 in various tissues by RT-PCR, and found that NDRG4 was highly expressed in chicken brain and heart, whereas lowly but detectable in thymus. The mRNA expression of this gene in chicken liver, spleen, lung and muscle was rarely detectable under present experimental conditions.