Channel properties of the splicing isoforms of the olfactory calcium-activated chloride channel Anoctamin 2.
Channel properties of the splicing isoforms of the olfactory calcium-activated chloride channel Anoctamin 2.
复制标题
DOI：
10.1085/jgp.201210937
复制
发表时间：
2013-06
期刊：
影响因子：
--
通讯作者：
Reisert J
中科院分区：
文献类型：
--
作者：
Ponissery Saidu S;Stephan AB;Talaga AK;Zhao H;Reisert J
Anoctamin (ANO)2（或 TMEM16B）形成细胞膜 Ca2+ 激活的 Cl− 通道，存在于嗅觉受体神经元的纤毛、犁鼻微绒毛和光感受器突触末梢中。 Ano2 转录物的选择性剪接产生多个变体，其中嗅觉变体跳过外显子 14 并具有外显子 4 的选择性剪接。在本研究中，进行 cDNA 末端分析的 5' 快速扩增来表征嗅觉 Ano2 转录物的 5' 末端，这表明嗅觉上皮中最丰富的 Ano2 转录物包含编码翻译起始位点的新起始外显子，而公开的序列变体具有替代且更长的 5' 末端，但丰度较低。有了两个可选择的起始外显子和外显子 4 的可选择剪接，四种嗅觉 ANO2 同种型就可能出现。在表达这些亚型的转染 HEK293T 细胞中进行的膜片钳实验表明，N 末端序列影响 Ca2+ 敏感性，并且外显子 4 编码的序列是形成功能通道所必需的。两种主要亚型（一种具有外显子 4 序列，一种不具有外显子 4 序列）的共表达以及两种较稀有亚型的共表达显示了通道特性的改变，表明不同的亚型彼此相互作用。此外，从主要亚型的共表达中观察到的通道特性更好地概括了天然通道特性，这表明天然通道可能由两个或多个剪接亚型组成，它们充当共同塑造通道特性的亚基。
Anoctamin (ANO)2 (or TMEM16B) forms a cell membrane Ca2+-activated Cl− channel that is present in cilia of olfactory receptor neurons, vomeronasal microvilli, and photoreceptor synaptic terminals. Alternative splicing of Ano2 transcripts generates multiple variants with the olfactory variants skipping exon 14 and having alternative splicing of exon 4. In the present study, 5′ rapid amplification of cDNA ends analysis was conducted to characterize the 5′ end of olfactory Ano2 transcripts, which showed that the most abundant Ano2 transcripts in the olfactory epithelium contain a novel starting exon that encodes a translation initiation site, whereas transcripts of the publically available sequence variant, which has an alternative and longer 5′ end, were present in lower abundance. With two alternative starting exons and alternative splicing of exon 4, four olfactory ANO2 isoforms are thus possible. Patch-clamp experiments in transfected HEK293T cells expressing these isoforms showed that N-terminal sequences affect Ca2+ sensitivity and that the exon 4–encoded sequence is required to form functional channels. Coexpression of the two predominant isoforms, one with and one without the exon 4 sequence, as well as coexpression of the two rarer isoforms showed alterations in channel properties, indicating that different isoforms interact with each other. Furthermore, channel properties observed from the coexpression of the predominant isoforms better recapitulated the native channel properties, suggesting that the native channel may be composed of two or more splicing isoforms acting as subunits that together shape the channel properties.
登录
查看更多内容
CA激活的CL通道及其在大鼠嗅觉受体神经元中的控制。
影响因子：
3.8
作者：
Reisert, Johannes;Bauer, Paul J;Yau, King-Wai;Frings, Stephan
通讯作者：
Frings, Stephan
影响因子：
4.8
作者：
Ferrera, Loretta;Caputo, Antonella;Galietta, Luis J. V.
通讯作者：
Galietta, Luis J. V.
anoctamin/tmem16 Cl-通道家族中的 ANO 3-7 是细胞内蛋白
影响因子：
5.5
作者：
Duran, Charity;Qu, Zhiqiang;Hartzell, H. Criss
通讯作者：
Hartzell, H. Criss
影响因子：
--
作者：
O'Driscoll KE;Pipe RA;Britton FC
通讯作者：
Britton FC
影响因子：
3.5
作者：
Rasche, Sebastian;Toetter, Bastian;Neuhaus, Eva M.
通讯作者：
Neuhaus, Eva M.