Lima A A, Ságio S A, Chalfun-Júnior A, Paiva L V
Departamento de Biologia, Universidade Federal de Lavras, Lavras, MG, Brasil.
Genet Mol Res. 2011 Jun 28;10(2):1277-89. doi: 10.4238/vol10-2gmr1314.
The plant hormone ethylene is involved in several developmental and physiological processes in plants, including senescence, fruit ripening and organ abscission, as well as in biotic and abiotic stress responses. Initiation of these processes involves complex regulation of both ethylene biosynthesis and the ability of cells to perceive the hormone and respond in an appropriate manner, a process which is regulated both spatially and temporally. Ethylene is a gaseous hormone whose sensitivity is a key factor to limiting its response in target cells. We made a search of the Coffee Expressed Sequence Tag (CAFEST) database for expressed sequence tags related to known elements of the ethylene signaling pathway. Sequences showing a reliable similarity were clusterized, annotated and analyzed for conserved domains. Multiple alignments comprising the sequences that we found and sequences of ethylene signaling elements from other species were made, and their phylogeny was assessed by phylogenetic trees constructed with the MEGA4 software. The expression profile was assessed by in silico Northern blot analysis performed using the Cluster and TreeView programs. The CAFEST database was found to have a large number of sequences related to previously described ethylene signaling pathway elements, allowing identification of putative members from almost every step of this pathway. The phylogenetic trees demonstrated high similarity between the sequences found in the CAFEST and those from other species, and the electronic Northern blot analysis detected their expression in various tissues, development stages and stress conditions.
植物激素乙烯参与植物的多个发育和生理过程，包括衰老、果实成熟和器官脱落，以及生物和非生物胁迫反应。这些过程的启动涉及乙烯生物合成以及细胞感知该激素并以适当方式做出反应的能力的复杂调控，这一过程在空间和时间上均受到调控。乙烯是一种气态激素，其敏感性是限制其在靶细胞中反应的关键因素。我们在咖啡表达序列标签（CAFEST）数据库中搜索与乙烯信号通路已知元件相关的表达序列标签。对显示出可靠相似性的序列进行聚类、注释并分析其保守结构域。将我们找到的序列与来自其他物种的乙烯信号元件序列进行多重比对，并使用MEGA4软件构建系统发育树来评估它们的系统发育关系。通过使用Cluster和TreeView程序进行的电子Northern印迹分析来评估表达谱。发现CAFEST数据库中有大量与先前描述的乙烯信号通路元件相关的序列，从而能够鉴定出该通路几乎每个步骤的推定成员。系统发育树表明，在CAFEST中发现的序列与来自其他物种的序列高度相似，并且电子Northern印迹分析检测到它们在各种组织、发育阶段和胁迫条件下的表达。
