CRISPR-Cas9 Reveals Genes Involved in Rice Heading Date

Additional genes involved in the control of the heading date of rice were identified using CRISPR-Cas9 technology. The study conducted by Huazhong Agricultural University scientists is published in the Journal of Integrative Plant Biology.

The CO, CO-LIKE, and TOC1 (CCT) domain proteins are known to regulate flowering time in many plant species. However, in rice, only a few out of the 41 CCT genes were shown to regulate heading date. To identify more genes involved in this mechanism, the researchers grouped the CCT family genes according to their diurnal expression patterns.

Using CRISPR-Cas9, knockout mutants of the entire gene family were produced. Analysis showed that OsCCT22, OsCCT38, and OsCCT41 restrain heading under long‐day conditions and boost heading under short‐day conditions. OsCCT03 helps heading under both conditions and increases the expression of Heading date 1 (Hd1) and Early heading date 1 (Ehd1) genes.

With the additional genes, 18 CCT domain-containing genes involved in heading date are now known to date, providing more gene combinations for the development of rice varieties with a given heading date.

Read more findings in the Journal of Integrative Plant Biology.