Although DNA methylation primarily represses TEs, it also represses select genes that are methylated in plant body tissues but demethylated by DNA glycosylases (DNGs) in endosperm or pollen. Either one of two DNGs, MATERNAL DEREPRESSION OF R1 (MDR1) or DNG102, is essential for pollen viability in maize. Using single-pollen mRNA sequencing on pollen-segregating mutations in both genes, we identify 58 candidate DNG target genes that account for 11.
View Article and Find Full Text PDFAlthough DNA methylation primarily represses TEs, it also represses select genes that are methylated in plant body tissues but demethylated by DNA glycosylases (DNGs) in endosperm or pollen. Activity of either one of two DNGs, MDR1 or DNG102, is essential for pollen viability in maize. Using single-pollen mRNA sequencing on pollen segregating mutations in both genes, we identified 58 candidate DNG target genes that account for 11.
View Article and Find Full Text PDFMembers of the La-related protein family (LARPs) contain a conserved La module, which has been associated with RNA-binding activity. Expression of the maize gene GRMZM2G323499/Zm00001d018613, a member of the LARP family, is highly specific to pollen, based on both transcriptomic and proteomic assays. This suggests a pollen-specific RNA regulatory function for the protein, designated ZmLARP6c1 based on sequence similarity to the LARP6 subfamily in .
View Article and Find Full Text PDFHigh-throughput phenotyping systems are powerful, dramatically changing our ability to document, measure, and detect biological phenomena. Here, we describe a cost-effective combination of a custom-built imaging platform and deep-learning-based computer vision pipeline. A minimal version of the maize (Zea mays) ear scanner was built with low-cost and readily available parts.
View Article and Find Full Text PDFIn flowering plants, gene expression in the haploid male gametophyte (pollen) is essential for sperm delivery and double fertilization. Pollen also undergoes dynamic epigenetic regulation of expression from transposable elements (TEs), but how this process interacts with gene expression is not clearly understood. To explore relationships among these processes, we quantified transcript levels in four male reproductive stages of maize (tassel primordia, microspores, mature pollen, and sperm cells) via RNA-seq.
View Article and Find Full Text PDFThe exocyst, a conserved, octameric protein complex, helps mediate secretion at the plasma membrane, facilitating specific developmental processes that include control of root meristem size, cell elongation, and tip growth. A genetic screen for second-site enhancers in Arabidopsis identified NEW ENHANCER of ROOT DWARFISM1 (NERD1) as an exocyst interactor. Mutations in NERD1 combined with weak exocyst mutations in SEC8 and EXO70A1 result in a synergistic reduction in root growth.
View Article and Find Full Text PDFBackground: Plant gametophytes play central roles in sexual reproduction. A hallmark of the plant life cycle is that gene expression is required in the haploid gametophytes. Consequently, many mutant phenotypes are expressed in this phase.
View Article and Find Full Text PDFPlant Rho family GTPases (ROPs) have been investigated primarily for their functions in polarized cell growth. We previously showed that the maize (Zea mays) Leu-rich repeat receptor-like protein PANGLOSS1 (PAN1) promotes the polarization of asymmetric subsidiary mother cell (SMC) divisions during stomatal development. Here, we show that maize Type I ROPs 2 and 9 function together with PAN1 in this process.
View Article and Find Full Text PDFGeneration and expression of cell polarity in brown algal zygotes of the Fucales involve regulation of the actin cytoskeleton and localized secretion. We used degenerate PCR to isolate cDNAs that encode two small GTPases, FdRac1 and FdRab8, from zygotes of Fucus distichus (L.) Powell.
View Article and Find Full Text PDFRop small GTPases are plant-specific signaling proteins with roles in pollen and vegetative cell growth, abscisic acid signal transduction, stress responses, and pathogen resistance. We have characterized the rop family in the monocots maize (Zea mays) and rice (Oryza sativa). The maize genome contains at least nine expressed rops, and the fully sequenced rice genome has seven.
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