TY  - EJOU
AU  - Zhang, Lin 
AU  - Xie, Dong 
AU  - Bian, Zhong 
AU  - Zou, Yiting 
AU  - Zhou, Han 
AU  - Cai, Wenlu 
AU  - Yeilaghi, Hadi 
AU  - Fan, Xiaolei 
AU  - Zhang, Changquan 
AU  - Liu, Qiaoquan 

TI  - Exploration and Validation of the Potential Downstream Genes Underlying <i>ipa1-2D</i> Locus for Rice Panicle Branching
T2  - Phyton-International Journal of Experimental Botany

PY  - 2021
VL  - 90
IS  - 3
SN  - 1851-5657

AB  - In recent years, some super hybrid rice varieties were bred with strong culms and large panicles, which are mainly
contributed by the <i>ipa1-2D</i> locus. A gain-of-function allele of <i>OsSPL14</i> is the <i>ipa1-2D</i> and it can greatly increase
the panicle primary branch number. However, the key downstream genes mediating this trait variation are not
fully explored. In this study, we developed high-quality near-isogenic lines (NILs) with a difference of only
30 kb chromosomal segment covering the <i>ipa1-2D</i> locus. Using the NILs, we explored the impact of <i>ipa1-2D</i>
on five sequential stages of early inflorescence development, and found that the locus can greatly enhance the
initiation of primary branch meristems. A transcriptomic analysis was performed to unveil the downstream molecular network of <i>ipa1-2D</i>, and 87 genes were found differentially expressed, many of which are involved in metabolism and catalysis processes. In addition, transgenic lines of overexpression and RNA interference were
generated to shape different levels of <i>OsSPL14</i>. They were also used to validate the expression variation explored
by transcriptome. Based on the gene annotation, twelve potential downstream targets of <i>ipa1-2D</i> were selected,
and their expression variation was confirmed by qRT-PCR analysis both in NILs and transgenic lines. This
research expands the molecular network underlying <i>ipa1-2D</i> and provides novel gene information which might
be involved in the control of panicle branching. We discussed the potential function of identified genes and highlighted their values for future function exploration and breeding application.
KW  - Rice; <i>ipa1-2D</i>; panicle branching; inflorescence meristems; gene expression

DO  - 10.32604/phyton.2021.015229