Wang Min, Li Haijing, Zhang Xinhao, Yang Li, Liu Yu, Liu Shuqin, Sun Yujiang, Zhao Chunjiang
College of Animal Science and Technology, China Agricultural University, Beijing, China.
Equine Center, China Agricultural University, Beijing, China.
Anim Genet. 2022 Jun;53(3):368-379. doi: 10.1111/age.13196. Epub 2022 Mar 21.
The aim of the present study was to analyze the main factors that have a significant impact on skin thickness, and to further identify the genes and signaling pathways regulating skin growth by RNA-seq in Dezhou donkeys. Skin samples from different body regions of 15 slaughtered donkeys were obtained to study variations in skin thickness over the bodies. Skin thickness data for another 514 donkeys was obtained by minimally invasive skin sampling from the back, and measurements of the donkeys' body size traits and pedigree data were also collected. These data were used to analyze changes in skin thickness and estimate genetic parameters. In addition, transcriptomic analysis was conducted on the skin tissues of individuals from two groups with significant differences in skin thickness. Our results showed that skin thickness over the bodies ranged from 1.08 to 4.36 mm. The skin from the back was the thickest and had the highest correlation with that of other regions of the body. The skin thickness decreased from the back to the side of the ventral abdomen, and the skin thickness on the limbs increased from the proximal end to the distal end. The results also showed that the skin from the same body regions of jacks was thicker than that of jennies in the same age group. The skin thickness of jennies increased from birth to the age of 2 and then clearly decreased after 2 years of age. The estimated heritability of skin thickness was 0.15, and the genetic correlations between skin thickness and body size traits were negligible. Transcriptome analysis showed that the thick-skin group had 65 up-regulated genes and 38 down-regulated genes compared with the thin-skin group. The differentially expressed genes were highly enriched in epidermal development and cell adhesion molecule signaling pathways. We identified the candidate genes responsible for variations in skin thickness in the Dezhou donkey, including KRT10, KRT1, CLDN9, MHCII and MMP28. These results contribute to a better understanding of the growth and development of donkey skin, reveal the molecular mechanism responsible for donkey skin thickness and suggest directions for genetic selection in the Dezhou donkey population.
本研究的目的是分析对皮肤厚度有显著影响的主要因素，并通过RNA测序进一步鉴定德州驴中调节皮肤生长的基因和信号通路。采集了15头屠宰驴不同身体部位的皮肤样本，以研究身体各部位皮肤厚度的差异。通过对另外514头驴背部进行微创皮肤采样获得皮肤厚度数据，并收集了这些驴的体尺性状测量数据和系谱数据。这些数据用于分析皮肤厚度的变化并估计遗传参数。此外，对皮肤厚度有显著差异的两组个体的皮肤组织进行了转录组分析。我们的结果表明，身体各部位的皮肤厚度在1.08至4.36毫米之间。背部皮肤最厚，与身体其他部位的皮肤相关性最高。皮肤厚度从背部到腹侧腹部侧面逐渐减小，四肢皮肤厚度从近端到远端逐渐增加。结果还表明，在同一年龄组中，公驴相同身体部位的皮肤比母驴厚。母驴的皮肤厚度从出生到2岁增加，2岁后明显下降。皮肤厚度的估计遗传力为0.15，皮肤厚度与体尺性状之间的遗传相关性可忽略不计。转录组分析表明，与薄皮组相比，厚皮组有65个上调基因和38个下调基因。差异表达基因在表皮发育和细胞粘附分子信号通路中高度富集。我们鉴定出了德州驴皮肤厚度变异的候选基因，包括KRT10、KRT1、CLDN9、MHCII和MMP28。这些结果有助于更好地理解驴皮肤的生长发育，揭示驴皮肤厚度的分子机制，并为德州驴群体的遗传选择提供方向。
