Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, -110067, India.
J Cell Biochem. 2013 Sep;114(9):2071-81. doi: 10.1002/jcb.24552.
It is imperative to understand the mechanisms of growth and development in higher plants for improving plant adaptation during different developmental stages. Plant microRNAs (miRs) play crucial regulatory roles in various developmental processes. As many as 15 miR families having multiple members are known to regulate plant development, yet the spatio-temporal expression patterns of individual members are not fully characterized. It is likely that different members of miR families can make specific contributions to the spatio-temporal control of targets. To understand the functional complexity of miRs and the amount of degeneracy existing in miR-mediated regulation of differentiated but developing tissues, we have identified the Osa-miR-sequences that are expressed in specific tissues. We adopted the approach of comparative miR profiling using next-generation sequencing technology followed by experimental validation. It was observed that 59 Osa-miR-sequences show tissue-preferential expression in local basmati rice variety; while 126 miRs belonging to 81 families are differentially regulated in these tissues. The 21 nt miRs were predominant in all tissues, but the 24 nt miRs were the most abundantly expressed. This indicates that target cleavage and chromatin state regulation are involved in organ development. This study also identified the expression patterns of individual members of Osa-miR families that were common and divergent between the indica and japonica rice varieties. The expression patterns of the predicted targets were also analyzed. The possible implications of the miR distribution patterns with respect to the regulation of their respective targets are discussed.
了解高等植物生长和发育的机制对于提高植物在不同发育阶段的适应能力至关重要。植物 microRNAs（miRs）在各种发育过程中发挥着关键的调节作用。多达 15 个 miR 家族拥有多个成员，已知它们可以调节植物的发育，但单个成员的时空表达模式尚未完全描述。不同的 miR 家族成员可能会对靶标时空调控做出特定的贡献。为了理解 miRs 的功能复杂性以及 miR 介导的对分化但发育组织的调控中存在的冗余程度，我们已经鉴定了在特定组织中表达的 Osa-miR 序列。我们采用了比较 miR 谱分析的方法，使用下一代测序技术，然后进行实验验证。结果观察到 59 个 Osa-miR 序列在当地巴斯马蒂水稻品种中表现出组织偏好表达；而 81 个家族的 126 个 miRs 在这些组织中表现出差异调节。21 nt 的 miRs 在所有组织中都占优势，但 24 nt 的 miRs 表达最丰富。这表明靶标切割和染色质状态调节参与了器官发育。本研究还鉴定了 Osa-miR 家族中个别成员在籼稻和粳稻品种之间的共同和不同表达模式。还分析了预测靶标的表达模式。讨论了 miR 分布模式对其各自靶标的调节的可能影响。
