Monoallelic gene expression refers to the phenomenon that all transcripts of a gene in a cell are expressed from only one of the two alleles in a diploid organism. Based on the observations in bulk transcriptome analyses, two possible molecular mechanisms, parent-of-origin effects and allelic repression, have been proposed to cause monoallelic gene expression. Because monoallelic gene expression in individual cells may not always be observed in bulk transcriptome analyses, single-cell transcriptome analyses can significantly promote our understanding on monoallelic gene expression.
A recent collaborative research from the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences reported widespread monoallelic gene expression in plant cells.
Researchers from JIAO Yuling’s lab applied a single-cell RNA-seq protocol to rice mesophyll cells in indica (93-11) and japonica (Nipponbare) inbred lines, as well as their F1 reciprocal hybrids. Researchers from QIAN Wenfeng’s lab and WANG Xiujie’s lab estimated allelic expression levels in individual cells based on SNPs between 93-11 and Nipponbare. By comparing the expression level between two alleles, they defined genes exhibit monoallelic expression in individual cells. Surprisingly, ~68% of expressed genes were monoallelically expressed in individual rice mesophyll cells.
They further investigated the molecular mechanism of monoallelic expression and found that stochastic and independent transcription of two alleles could largely explain the observed pattern of monoallelic expression.
This work entitled “Single-cell transcriptome analysis reveals widespread monoallelic gene expression in individual rice mesophyll cells”, has been published on
Science Bulletin (
DOI:10.1016/j.scib.2017.09.011).
This work was funded by the National Basic Research Program of China (973 Program), the National Program for Support of Top-Notch Young Professionals, the Recruitment Program of Global Youth Experts, and the State Key Laboratory of Plant Genomics.
Figure. Pervasive monoallelic gene expression was observed in rice mesophyll cells. (Image by IGDB)
Contacts:
Drs. JIAO Yuling and QIAN Wenfeng
Institute of Genetics and Developmental Biology, Chinese Academy of Sciences
