1Department of Agricultural and-Food Sciences (DISTAL),Bologna University,Viale G. Fanin,46,40127 Bologna,Italy.
2Department of Veterinary Medical Sciences (DIMEVET),Bologna University,Via Tolara di Sopra,50,40064 Ozzano dell'Emilia (BO),Italy.
Animal. 2018 Jun;12(6):1135-1143. doi: 10.1017/S1751731117002804. Epub 2017 Nov 2.
The growing request for healthier fatty acid composition of animal products is raising the necessity of a deeper knowledge of the main factors controlling fatty acids storage in muscle and backfat. Perilipin (PLIN) 5, and the whole Perilipin family, seem to play a crucial role in the regulation of lipids deposition as code for proteins coating intracellular lipid droplets surface. Nevertheless, the knowledge of these genes in pig is still incomplete. The present research was aimed at investigating in different pig breeds the PLIN5 gene, analysing its expression level and the associations of the variability in its downstream gene region with pork meat and carcass quality traits. Moreover, the PLIN5 protein localisation in porcine skeletal muscle was investigated through immunofluorescence, resulting to be widespread in Semimembranosus muscle (SM) myofibers. The identified single nucleotide polymorphism (SNP) rs327694326 (NC_010444.4:g.74314701T>C) located in PLIN5 downstream region was analysed in different pig populations, represented by 512 Italian Large White (ILW) pigs, 300 Italian Duroc (IDU) samples, 100 Italian Landrace, 100 Pietrain and 60 pigs belonging to three Italian native breeds (20 samples of Cinta Senese, 20 Calabrese and 20 Casertana pigs). The C allele was found in ILW, IDU and Pietrain pigs. In ILW pigs this SNP showed results indicating a possible association with oleic and cis-vaccenic fatty acid contents in backfat tissue. Furthermore, as PLINs are known to regulate lipases activity, we tested if the rs327694326 SNP was associated with differences in Hormone-sensitive lipase (LIPE) gene expression levels. In SM of ILW pigs, PLIN5 C allele was associated with significantly lower LIPE transcription levels than T allele (P=0.02 for Student's t test of TT v. CT samples, P<0.0001 for TT v. CC pigs), whereas in IDU breed no significant difference was noticed in LIPE transcription levels between TT and TC animals. The results may suggest that variations in the PLIN5 sequence may be linked to LIPE expression through a still poorly known regulative molecular process.
对动物产品中更健康脂肪酸组成的需求不断增长，这使得我们有必要更深入地了解控制肌肉和背脂中脂肪酸储存的主要因素。脂滴包被蛋白 5（ perilipin 5，PLIN5）及其整个 perilipin 家族似乎在调节脂质沉积方面发挥着关键作用，因为它是覆盖细胞内脂滴表面的蛋白质的编码基因。然而，目前我们对猪中这些基因的了解还不完全。本研究旨在调查不同猪品种中 PLIN5 基因，分析其表达水平，并研究其下游基因区域的变异与猪肉和胴体质量性状的相关性。此外，还通过免疫荧光法研究了 PLIN5 蛋白在猪骨骼肌中的定位，结果表明其在半膜肌（SM）肌纤维中广泛存在。在所鉴定的单核苷酸多态性（SNP）rs327694326（NC_010444.4：g.74314701T>C）位于 PLIN5 下游区域，在不同的猪种群中进行了分析，这些种群代表了 512 头意大利大白猪（ILW）、300 头意大利杜洛克猪（IDU）、100 头意大利长白猪、100 头皮特兰猪和 60 头属于三个意大利本土品种（20 头 Cinta Senese 猪、20 头卡拉布里亚猪和 20 头卡塞塔猪）的猪。在 ILW、IDU 和皮特兰猪中发现了 C 等位基因。在 ILW 猪中，该 SNP 显示出与背脂组织中油酸和顺式vaccenic 脂肪酸含量可能相关的结果。此外，由于 PLINs 被认为可以调节脂肪酶的活性，我们测试了 rs327694326 SNP 是否与激素敏感脂肪酶（LIPE）基因表达水平的差异相关。在 ILW 猪的 SM 中，PLIN5 的 C 等位基因与 T 等位基因相比，LIPE 的转录水平明显更低（TT 与 CT 样本相比，学生 t 检验 P=0.02，TT 与 CC 猪相比，P<0.0001），而在 IDU 品种中，TT 和 TC 动物之间的 LIPE 转录水平没有显著差异。结果表明，PLIN5 序列的变异可能通过一个仍不太清楚的调控分子过程与 LIPE 的表达相关。
