Lv Mengqing, Mu Ji'an, Xing Ya, Zhou Xiaoyi, Ge Jing, Gong Daoqing, Geng Tuoyu, Zhao Minmeng
College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu Province, 225009, China.
Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, Jiangsu Province, 225009, China.
J Anim Sci. 2024 Jan 3;102. doi: 10.1093/jas/skae239.
Protein kinase A (PKA) plays an important role in cellular life activities. Recently, PKA was found to bind to the inhibitor of nuclear factor-kappaB (IκB), a key protein in the nuclear factor-kappaB (NF-κB) pathway, to form a complex involved in the regulation of inflammatory response. However, the role of PKA in the anti-inflammatory of goose fatty liver is still unclear. A total of 14 healthy 70-d-old male Lander geese were randomly divided into a control group and an overfeeding group. Inflammation level was analyzed by histopathological method in the liver. The mRNA and protein abundance of PKA and tumor necrosis factor-alpha (TNFα), as well as the ubiquitination level of PKA, were detected. Moreover, goose primary hepatocytes were cotreated with glucose, harringtonine, and carbobenzoxy-l-leucyl-l-leucyl-l-leucinal (MG132). Finally, the co-immunoprecipitated samples of PKA from the control and overfeeding group were used for protein mass spectrometry. The results showed that no difference in PKA mRNA expression was observed (P > 0.05), while the PKA protein level in the overfed group was significantly reduced (P < 0.05) when compared with the control group. The ubiquitination level of PKA was higher than that of the control group in fatty liver. The mRNA expression of PKA was elevated but protein abundance was reduced in goose primary hepatocytes with 200 mmol/L glucose treatment (P < 0.05). The PKA protein abundance was dramatically reduced in hepatocytes treated with harringtonine (P < 0.01) when compared with the glucose-supplemented group. Nevertheless, MG132 tended to alleviate the inhibitory effect of harringtonine on PKA protein abundance (P = 0.081). There was no significant difference in TNFα protein level among glucose-treated groups and control (P > 0.05). Protein mass spectrometry analysis showed that 29 and 76 interacting proteins of PKA were screened in goose normal and fatty liver, respectively. Validation showed that PKA interacted with the E3 ubiquitination ligases ring finger protein 135 (RNF135) and potassium channel modulatory factor 1 (KCMF1). In summary, glucose may inhibit the inflammatory response in goose fatty liver by increasing the ubiquitination level of PKA. Additionally, RNF135 and KCMF1 may be involved in the regulation of PKA ubiquitination level as E3 ubiquitination ligases.
蛋白激酶A（PKA）在细胞生命活动中发挥着重要作用。最近，发现PKA与核因子κB（NF-κB）通路中的关键蛋白核因子κB抑制蛋白（IκB）结合，形成参与炎症反应调节的复合物。然而，PKA在鹅脂肪肝抗炎中的作用仍不清楚。将14只70日龄健康雄性朗德鹅随机分为对照组和过量饲喂组。通过组织病理学方法分析肝脏中的炎症水平。检测PKA和肿瘤坏死因子-α（TNFα）的mRNA和蛋白丰度，以及PKA的泛素化水平。此外，将鹅原代肝细胞与葡萄糖、三尖杉酯碱和苄氧羰基-L-亮氨酰-L-亮氨酰-L-亮氨酸（MG132）共同处理。最后，将对照组和过量饲喂组的PKA免疫共沉淀样品用于蛋白质质谱分析。结果表明，PKA mRNA表达无差异（P>0.05），但与对照组相比，过量饲喂组的PKA蛋白水平显著降低（P<0.05）。脂肪肝中PKA的泛素化水平高于对照组。用200 mmol/L葡萄糖处理的鹅原代肝细胞中PKA的mRNA表达升高但蛋白丰度降低（P<0.0
