Plant Genomics

Biography

Biography: Muhammad Qasim Shahid

Abstract

Autotetraploid rice has a great      genetic potential      to increase the     rice production    , but lower pollen    fertility    is a major barrier in   its utilization. Intersubspecific autotetraploid    rice hybrids    showed greater   genetic variation   compared to their  diploid  counterparts. Here, we observed  the  pollen development and its relation with  seed  set in autotetraploid rice. Microgametogenesis in autotetraploid rice was similar to     diploid      rice, but different kinds of abnormalities, including     microspores degeneration   ,     cytoplasm shrinkage    and   abnormal cell walls  , were found in   auto tetraploid rice  . Many different kind s of   chromosomal abnormalities   were found during various development stages of polle n mother cell meiosis such as  chromosome lagging , chromosome straggling, pre-s  eparation of two chromosome set, randomly arranged     chromosome     on the equator, abnormal    spindle   , and incomplete/no separation of     cytokinesis   . We identified  meiosis-related or    meiosis-stage-specific genes    that were down-regulated in   polyploid rice  .  Gene ontology  analysis on the targets of up-r  egulated DEM showed that they were enriched in transport and membrane in pre-meiotic interphase, reproduction in meiosis, and  nucleotide binding  in single microspore stage. Quantitative RT-PCR was used to validate differentially  expressed genes  and microRNAs selected from functional categories based on the ge ne ontology analysis and t he results showed that their expression patterns were consistent with the microarray data and high-throughput sequencing, respectively. These findings provide a foundation for understanding the effect of polyploidy on meiosis-related genes and miRNAs expression patterns during pollen development that lead to low pollen fertility in autotetraploid rice.