Jiang Z, Li F, Wan Y, Han Z, Yuan W, Cao L, Deng Y, Peng X, Chen F, Fan X, Liu X, Dai G, Wang Y, Zeng Q, Shi Y, Zhou Z, Chen Y, Xu W, Luo S, Chen S, Ye X, Mo X, Wu X, Li Y
The Center for Heart Development, Hunan Normal University, Changsha 410081, Hunan, P.R. China.
Curr Mol Med. 2016;16(6):582-90. doi: 10.2174/1566524016666160607090012.
Longevity Assurance 5 (LASS5), a member of the LASS/Ceramide Synthases family, synthesizes C16-ceramide and is implicated in tumor biology. However, its precise role is not yet well understood. A yeast two-hybrid screen was performed using a human cDNA library to identify potential LASS5- interaction partners. One identified clone encodes succinate dehydrogenase subunit B (SDHB). Mammalian two-hybrid assays showed that LASS5 interacts with SDHB, and the result was also confirmed by GST pull-down and coimmunoprecipitation assays. The C-terminal fragment of SDHB was required for the interaction. LASS5 and SDHB were co-localized in COS-7 cells. LASS5 and SDHB expressions were found to be up-regulated in neuroglioma tissue. Transfection assays showed that LASS5 or SDHB expression repressed p53 or p21 reporter activity, respectively. Simultaneous LASS5 and SDHB expression resulted in stronger repression of p53 and p21 reporter activity, suggesting that LASS5 and SDHB interaction may synergistically affect transcriptional regulation of p53 and p21. Our data provide new molecular insights into potential roles of LASS5 and SDHB in tumor biology.
长寿保障蛋白5（LASS5）是LASS/神经酰胺合酶家族的成员之一，可合成C16 - 神经酰胺，并与肿瘤生物学相关。然而，其确切作用尚未完全明确。利用人cDNA文库进行酵母双杂交筛选，以鉴定潜在的LASS5相互作用伙伴。一个鉴定出的克隆编码琥珀酸脱氢酶亚基B（SDHB）。哺乳动物双杂交试验表明LASS5与SDHB相互作用，并且该结果也通过谷胱甘肽 - S - 转移酶（GST）下拉试验和免疫共沉淀试验得到证实。SDHB的C末端片段是相互作用所必需的。LASS5和SDHB在COS - 7细胞中共定位。研究发现LASS5和SDHB在神经胶质瘤组织中表达上调。转染试验表明，LASS5或SDHB的表达分别抑制p53或p21报告基因的活性。同时表达LASS5和SDHB会导致对p53和p21报告基因活性更强的抑制，这表明LASS5和SDHB的相互作用可能协同影响p53和p21的转录调控。我们的数据为LASS5和SDHB在肿瘤生物学中的潜在作用提供了新的分子见解。
