ASIP: TRANSCRIPTS AND EXPRESSION IN LLAMAS WITH DIFFERENT COAT COLOR

ANELLO M; DAVERIO M S; ROMERO S; VIDAL RIOJA LB; RENIERI C; DI ROCCO F

Lleida

Congreso; 37th International Society for Animal Genetics Conference; 2019

International Society for Animal Genetics

The Agoutí gene (ASIP) is one of the most important genes for coat color determination in mammals.It has a complex structure with different promoters and alternative non-coding first exons that aretranscribed into mRNAs with different 5´UTR. Studies in domestic animals indicate these transcriptscan control pigment distribution. Otherwise, white coat is usually produced by mutations in KIT, MITFand TYR genes. However, this phenotype has also been associated with overexpression of ASIP in somespecies. In llamas (Lama glama), the molecular mechanism responsible for white is still unknown. Wehave recently studied the coding regions of KIT, MITF, TYR and ASIP, but no mutations were found tobe associated with white coat in this species. Here, we characterized ASIP transcripts and studied theirexpression levels in the skin of llamas to further understand the role of ASIP in coat colordetermination. Skin biopsies were taken from white, pheomelanic (reddish brown) and eumelanic(black) llamas and total RNA was extracted. Then PCR-RACE was used to amplify the 5'UTRs of ASIPand these products were cloned and sequenced. Seven ASIP transcripts that differed in the 5?UTR werefound. Most of them exhibited a structure similar to some ASIP transcripts already described in othermammalian species and we identified the homologous exons 1A, 1A?, 2A, 3A, and 1C. Additionally, onetranscript (T6) presented a 5?UTR of 120 bp that showed similarity with NCOA6 gene. Then, we studiedthe global expression of ASIP by qPCR in the three phenotypic groups. White and brown groupsshowed an overexpression of ASIP in comparison to black (p