Exploring the Maintaining Period and the Differentially Expressed Genes between the Yellow and Black Stripes of the Juvenile Stripe in the Offspring of Wild Boar and Duroc.

Simple Summary: At birth, wild boars and their hybrid offspring usually have camouflage coat colors with juvenile stripes (the black/dark longitudinal stripes separated by yellow/light ones) on their back and two side flanks, and the juvenile stripes disappear at 4–5 months old. To study the mechanism of juvenile stripe maintenance, piglets with juvenile stripes were produced by crossing a wild boar with three Duroc sows. Through picture recording and pigment extraction, we observed that the stripe tended to disappear within approximately 70 days. Furthermore, whole-transcriptome comparison between two adjacent stripes (dark and light) on the back revealed that ZIC4, ssc-miR-532-3p and ENSSSCG00000056225 might play a role in the formation of stripes. The present study laid the foundation for future research on the molecular mechanisms underlying juvenile stripes. Coloration is a crucial trait that allows species to adapt and survive in different environments. Wild boars exhibit alternating black (dark) and yellow (light) longitudinal stripes on their back during their infancy (juvenile stripes), and as adults, they transform into uniform wild-type coat color. Aiming to record the procedure of juvenile stripes disappearing, piglets (WD) with juvenile stripes were produced by crossing a wild boar with Duroc sows, and photos of their coat color were taken from 20 d to 220 d. The pigments in the hairs from the black and yellow stripes were determined. Furthermore, the differentially expressed genes between the black and yellow stripes were investigated in 5 WD with the age of 30 d using whole-transcriptome sequencing to explore the genetic mechanism of the juvenile stripes. The juvenile stripes started to disappear at about 70 d, and stripes were not distinguished with the naked eye at about 160 d; that is, the juvenile stripe completely disappeared. A hotspot of a differentially expressing (DE) region was found on chromosome 13, containing/covering 2 of 13 DE genes and 8 of 10 DE lncRNAs in this region. A network among ZIC4, ssc-miR-532-3p, and ENSSSCG00000056225 might regulate the formation of juvenile stripes. Altogether, this study provides new insights into spatiotemporal coat color pattern. [ABSTRACT FROM AUTHOR]