Université de Franche-Comté, Laboratoire de Biochimie, EA3922, Estrogènes, Expression Génique et Pathologies du Système Nerveux Central, IFR133, U.F.R. Sciences et Techniques, Besançon, France.
Autophagy. 2011 Nov;7(11):1302-7. doi: 10.4161/auto.7.11.16723. Epub 2011 Nov 1.
Atg8 is a yeast protein involved in the autophagic process and in particular in the elongation of autophagosomes. In mammals, several orthologs have been identified and are classed into two subfamilies: the LC3 subfamily and the GABARAP subfamily, referred to simply as the LC3 or GABARAP families. GABARAPL1 (GABARAP-like protein 1), one of the proteins belonging to the GABARAP (GABA(A) receptor-associated protein) family, is highly expressed in the central nervous system and implicated in processes such as receptor and vesicle transport as well as autophagy. The proteins that make up the GABARAP family demonstrate conservation of their amino acid sequences and protein structures. In humans, GABARAPL1 shares 86% identity with GABARAP and 61% with GABARAPL2 (GATE-16). The identification of the individual proteins is thus very limited when working in vivo due to a lack of unique peptide sequences from which specific antibodies can be developed. Actually, and to our knowledge, there are no available antibodies on the market that are entirely specific to GABARAPL1 and the same may be true of the anti-GABARAP antibodies. In this study, we sought to examine the specificity of three antibodies targeted against different peptide sequences within GABARAPL1: CHEM-CENT (an antibody raised against a short peptide sequence within the center of the protein), PTG-NTER (an antibody raised against the N-terminus of the protein) and PTG-FL (an antibody raised against the full-length protein). The results described in this article demonstrate the importance of testing antibody specificity under the conditions for which it will be used experimentally, a caution that should be taken when studying the expression of the GABARAP family proteins.
Atg8 是一种参与自噬过程的酵母蛋白，特别是在自噬体的延伸中。在哺乳动物中，已经鉴定出几个同源物，并分为两个亚家族：LC3 亚家族和 GABARAP 亚家族，简称为 LC3 或 GABARAP 家族。GABARAPL1（GABARAP 样蛋白 1）是属于 GABARAP（GABA(A)受体相关蛋白）家族的蛋白质之一，在中枢神经系统中高度表达，参与受体和囊泡运输以及自噬等过程。构成 GABARAP 家族的蛋白质表现出其氨基酸序列和蛋白质结构的保守性。在人类中，GABARAPL1 与 GABARAP 共享 86%的同一性，与 GABARAPL2（GATE-16）共享 61%的同一性。由于缺乏可以开发特异性抗体的独特肽序列，因此在体内工作时，对单个蛋白质的鉴定非常有限。实际上，据我们所知，目前市场上没有完全针对 GABARAPL1 的抗体，抗 GABARAP 抗体也可能如此。在这项研究中，我们试图检查针对 GABARAPL1 内不同肽序列的三种抗体的特异性：CHEM-CENT（一种针对蛋白质中心内短肽序列的抗体）、PTG-NTER（一种针对蛋白质 N 末端的抗体）和 PTG-FL（一种针对全长蛋白质的抗体）。本文描述的结果表明，在将其用于实验的条件下测试抗体特异性的重要性，在研究 GABARAP 家族蛋白质的表达时应注意这一点。
