MicroRNA activity in the Arabidopsis male germline

• Published in: Journal of experimental botany Vol. 62; no. 5; pp. 1611 - 1620
• Main Authors: Borges, Filipe, Pereira, Patrícia A, Slotkin, R. Keith, Martienssen, Robert A, Becker, Jörg D
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.03.2011; Oxford University Press (OUP)
• Subjects: Arabidopsis; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Cell Differentiation - genetics; Developmental biology; Epigenesis, Genetic; Gametophytes; Gene Expression Regulation, Plant; Genes; Genes, Plant; Germ cells; Life Sciences; MicroRNA; MicroRNAs - metabolism; Plants; Pollen; Pollen - growth & development; Pollen - metabolism; REVIEW PAPER; Review Papers; RNA; RNA Interference; RNA, Plant - genetics; RNA, Plant - metabolism; RNA, Small Interfering - genetics; RNA, Small Interfering - metabolism; RNA-Binding Proteins - genetics; RNA-Binding Proteins - metabolism; Sequence Analysis, RNA; Small interfering RNA; Spermatozoa; RNA, Plant; Arabidopsis; Genes, Plant; Epigenesis, Genetic; RNA-Binding Proteins; Arabidopsis Proteins; Sequence Analysis, RNA; RNA Interference; MicroRNAs; Gene Expression Regulation, Plant; Cell Differentiation; RNA, Small Interfering; Pollen
• ISSN: 0022-0957; 1460-2431
• DOI: 10.1093/jxb/erq452

Most of the core proteins involved in the microRNA (miRNA) pathway in plants have been identified, and almost simultaneously hundreds of miRNA sequences processed in the Arabidopsis sporophyte have been discovered by exploiting next-generation sequencing technologies. However, there is very limited understanding about potentially distinct mechanisms of post-transcriptional regulation between different cell lineages. In this review the focus is on the Arabidopsis male gametophyte (pollen), where the germline differentiates after meiosis giving rise to the male gametes. Based on comparative analysis of miRNAs identified in sperm cells by in-depth sequencing, their possible functions during germ cell specification and beyond fertilization are discussed. In addition, 25 potentially novel miRNAs processed in sperm cells and pollen were identified, as well as enriched variations in the sequence length of known miRNAs, which might indicate subfunctionalization by association with a putative germline-specific Argonaute complex. ARGONAUTE 5 (AGO5), by close homology to AGO1 and localizing preferentially to the sperm cell cytoplasm in mature pollen, may be part of such a complex.