AUTHOR=Lin Wujian , Ren Tuanhui , Li Wangyu , Liu Manqing , He Danlin , Liang Shaodong , Luo Wen , Zhang Xiquan 

TITLE=Novel 61-bp Indel of RIN2 Is Associated With Fat and Hatching Weight Traits in Chickens

JOURNAL=Frontiers in Genetics

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2021.672888

DOI=10.3389/fgene.2021.672888

ISSN=1664-8021

ABSTRACT=<p>The Ras and Rab interactor 2 (<italic>RIN2</italic>) gene, which encodes RAS and Rab interacting protein 2, can interact with GTP-bound Rab5 and participate in early endocytosis. This study found a 61-bp insertion/deletion (indel) in the <italic>RIN2</italic> intron region, and 3 genotypes <italic>II</italic>, <italic>ID</italic>, and <italic>DD</italic> were observed. Genotype analysis of mutation sites was performed on 665 individuals from F<sub>2</sub> population and 8 chicken breeds. It was found that the indel existed in each breed and that yellow feathered chickens were mainly of the <italic>DD</italic> genotype. Correlation analysis of growth and carcass traits in the F<sub>2</sub> population of Xinghua and White Recessive Rock chickens showed that the 61-bp indel was significantly correlated with abdominal fat weight, abdominal fat rate, fat width, and hatching weight (<italic>P &lt;</italic> 0.05). <italic>RIN2</italic> mRNA was expressed in all the tested tissues, and its expression in abdominal fat was higher than that in other tissues. In addition, the expression of the <italic>RIN2</italic> mRNA in the abdominal fat of the <italic>DD</italic> genotype was significantly higher than that of the <italic>II</italic> genotype (<italic>P</italic> &lt; 0.05). The transcriptional activity results showed that the luciferase activity of the pGL3-DD vector was significantly higher than that of the pGL3-II vector (<italic>P</italic> &lt; 0.01). Moreover, the results indicate that the polymorphisms in transcription factor binding sites (TFBSs) of 61-bp indel may affect the transcriptional activity of <italic>RIN2</italic>, and thus alter fat traits in chicken. The results of this study showed that the 61-bp indel was closely related to abdominal fat-related and hatching weight traits of chickens, which may have reference value for molecular marker-assisted selection of chickens.</p>