Project description:There are multiple types of small RNAs that may affect rice pollen’s development. To investigate the small RNA populations’ change during rice pollen development, 13-40 nt RNA were extracted from uninucleate microspores (UNM) and bicellular pollen (BCP) for high throughput sequencing. Together with our laboratory’s previous published rice tricellular pollen (TCP) small RNA sequencing data (GSM722128), sharp increase of tRNA fragments (tRFs) in BCP stage and a slightly decreased tRFs in TCP were found. Among which, new lengths of tRFs were also discovered. Our work accomplished the knowledge about tRFs in rice pollen development.
Project description:The profiling was conducted with the Rice 3'-Tiling 135k Microarray designed from 31,439 genes deposited at IRGSP, RAP2 database (http://rapdb.lab.nig.ac.jp). We have identified and characterized a T-DNA insert rice mutant (Osfuct) with loss of α1,3-fucosyltransferase function. Matrix-assisted laser desorption/ionization time-of-flight analyses of the N-glycan revealed the lack of α1,3-fucose in the N-glycan structure of rice Osfuct mutant. The mutant displayed the pleiotropic developmental defects such as diminished growth, shorter plant height, less number of tillers, shorter panicle lengths and internode, impaired anther and pollen development. In addition, the anther was curved, pollen grains shapes were shriveled, pollen viability and pollen number per anther was dramatically decreased in Osfuct mutant. The complementation test of Osfuct mutant clearly exhibited that the phenotype is caused by the loss of α1,3-fucosyltransferase function bescause complementation line is rescued. Transcriptome profiling data revealed that several genes essential in plant developmental processes were significantly altered in Osfuct mutant including protein kinases, transcription factors, genes involved in metabolism, genes related to protein synthesis and hypothetical proteins. Moreover, Osfuct mutant exhibited the enhanced salt insensitivity. Taken together, these findings demonstrated that Osfuct plays a critical role in growth, anther, pollen development and salt stress response.
Project description:In order to identify new miRNAs, NAT-siRNAs and possibly abiotic-stress regulated small RNAs in rice, three small RNA libraries were constructed from control rice seedlings and seedlings exposed to drought or salt stress, and then subjected to pyrosequencing.
Project description:- Pollen tube growth is important process for successful double fertilization, which is critical for grain yield in crop plants. Despite much progress in identification of rapid alkalization factors (RALFs) which serve as ligand for signaling transduction during fertilization in Arabidopsis, there is no functional study of RALF in mono-cotyledon plant. - We functionally characterized two pollen specific RALF in rice (Oryza sativa) using multiple CRISPR/Cas9 induced loss-of-function mutants, peptide treatment, expression analyses, tag reporter lines. - OsRALF17 is specifically expressed in pollen and pollen tube as the strongest level among 41 RALF members in rice. Exogenously applied OsRALF17 inhibits pollen tube germination and elongation at high concentration, but enhances tube elongation at low concentration, indicating the regulation of growth balance. Double mutant of OsRALF17 with OsRALF19 exhibit almost male sterile, with defect on pollen germination and tube elongation. - Our study revealed that functionally-redundant OsRALF17 and 19 peptides binds to the OsMTD2, CrRLK1L family member, and transmits ROS signal for pollen tube germination and integrity maintenance in rice. We provide new insights into the role of RALF and expanding our understanding of the biological role of RALF in regulating rice fertilization.
Project description:The small RNAs presented here were produced as a preliminary exploration of small RNAs in rice, and as such, various tissues and stress conditions were sampled. Small RNAs present in these samples were all mapped to the rice genome TIGR version 5. The total number of distinct mapped sequences are 12879 for Run 1 and 88508 for Run 2. The total number of sequence reads were respectively 70406 and 191682. The datasets contain Oryza sativa var Nipponbar endogenous small RNA sequences in the size range 18 to 34 nt. Plants were grown in a Conviron Environmental Chamber at high light intensity using both high pressure sodium and metal halide lamps for 10.5 hr at 28 degrees C and for 13.5 hr at 26 degrees C in the dark. RNA was extracted from rice tissues at various stages of development and under different abiotic and biotic stresses. The small RNAs presented here were all mapped to the rice genome TIGR version 5. The total number of distinct mapped sequences are 12879 for Run 1 and 88508 for Run 2. The total number of sequence reads were respectively 70406 and 191682.
Project description:MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) regulate gene expression in eukaryotes. Plant miRNAs modulate their targets mainly via messenger RNA (mRNA) cleavage. Small RNA targets have been extensively investigated in Arabidopsis using computational prediction, experimental validation, and degradome sequencing. However, small RNA targets are largely unknown in rice (Oryza sativa). Here, we report global identification of small RNA targets using high throughput degradome sequencing in the rice indica cultivar 93-11 (Oryza sativa L. ssp. indica). 177 transcripts targeted by total of 87 unique miRNAs were identified. Of targets for the conserved miRNAs between Arabidopsis and rice, transcription factors comprise around 70% (58 in 82), indicating that these miRNAs act as masters of gene regulatory nodes in rice. In contrast, non-conserved miRNAs targeted diverse genes which provide more complex regulatory networks. In addition, 5 AUXIN RESPONSE FACTORS (ARF) cleaved by the TAS3 derived ta-siRNAs were also detected. A total of 40 sRNA targets were further validated via RNA ligase-mediated 5’ rapid amplification of cDNA ends (RLM 5’-RACE). Our degradome results present a detailed sRNA-target interaction atlas, which provides a guide for the study of the roles of sRNAs and their targets in rice.