Maternal small RNAs mediate spatial-temporal regulation of gene expression, imprinting, and seed development in Arabidopsis

• DOI: 10.1073/pnas.1807621116
• Publication Date: 2019-01-29T01:21:41Z
• Authors: Ryan C. Kirkbride; Jie Lu; Changqing Zhang; Rebecca A. Mosher; David C. Baulcombe; Z. Jeffrey Chen
• Keywords: Genomic Imprinting; Trans-acting siRNA

Arabidopsis seed development involves maternal small interfering RNAs (siRNAs) that induce RNA-directed DNA methylation (RdDM) through the NRPD1 -mediated pathway. To investigate their biological functions, we characterized siRNAs in endosperm and coat were separated by laser-capture microdissection (LCM) reciprocal genetic crosses with an nrpd1 mutant. We also monitored spatial-temporal activity of pathway on using AGO4:GFP::AGO4 (promoter:GFP::protein) reporter promoter:GUS sensors siRNA-mediated silencing. From these approaches, identified four distinct groups siRNA loci dependent or independent allele coat. A group maternally expressed -siRNA targets endosperm-preferred genes, including those encoding AGAMOUS-LIKE (AGL) transcription factors. Using translational promoter:AGL::GUS constructs as sensors, demonstrate spatial temporal expression patterns genes are regulated irrespective complete silencing ( AGL91 ) incomplete AGL40 target genes. Moreover, altered siRNA-targeted affects size. propose corresponding could account for parent-of-origin effects interploidy hybrid crosses. These analyses reconcile previous studies imprinted gene during development.