Porcine dorfin: molecular cloning of the RNF19 gene, sequence comparison, mapping and expression analysis.

Dorfin, encoded by the RNF19 gene, is a protein containing two RING finger motifs. Dorfin functions as an E3 ubiquitin ligase that interacts with UBE2L3/UBCH7 and UBE2E2/UBCH8, but not other ubiquitin-conjugating enzymes. Dorfin is found expressed in Lewy bodies, neuronal protein inclusions occurring in Parkinson's disease brains. This work reports the cloning and analysis of the porcine (Sus scrofa) homologue of dorfin. The RNF19 cDNA encoding dorfin was amplified by reverse transcriptase polymerase chain reaction (RT-PCR) using oligonucleotide primers derived from in silico sequences. The porcine RNF19 cDNA codes for a protein of 838 amino acids which shows a very high similarity to human (97 %) and mouse (93 %) dorfin. The genomic organization of the porcine RNF19 gene is very similar to its human counterpart. Expression analysis by RT-PCR demonstrated that the porcine RNF19 transcript was observed in all organs and tissues examined, although differentially expressed. The highest expression of RNF19 mRNA was observed in cerebellum, heart, frontal cortex and muscle. RNF19 transcript was detected as early as 60 days of gestation in many different brain areas. Radiation hybrid mapping data indicate that the porcine RNF19 gene maps to chromosome 4 (4p11-p12). This particular map location is fully consistent with the currently known conservation of genome organization between human and pig and provides further confirmation that we have characterized the porcine homologue of the human RNF19.