PT  - JOURNAL ARTICLE
AU  - Chandan Roy
AU  - Salman Sahid
AU  - Riddhi Datta
AU  - Soumitra Paul
TI  - Spatial distribution of the lectin protein <em>Os</em>r40g3 determines its dual regulatory function in imparting salinity tolerance while impeding seed development in rice
AID  - 10.1101/2020.04.26.062158
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.04.26.062158
4099  - http://biorxiv.org/content/early/2020/04/27/2020.04.26.062158.short
4100  - http://biorxiv.org/content/early/2020/04/27/2020.04.26.062158.full
AB  - While the role of OsR40 family of lectin proteins in osmotic stress has long been known, their mechanism of stress tolerance has not yet been explored. Among them, the expression of Osr40g3 was most strongly induced in response to salt stress. Here, we report that Osr40g3 plays a dual role in regulating salinity tolerance as well as seed development in rice. The overexpression of Osr40g3 under control of a constitutive promoter significantly improved salinity tolerance but impaired seed development in transgenic rice. Remarkably, transgenic Arabidopsis ectopically expressing Osr40g3 exhibited enhanced salinity tolerance but produced seeds normally. It was further confirmed that this Osr40g3-mediated impairment in seed development was due to pollen sterility in the transgenic rice while the pistils remained unaffected. The gene further displayed a precise tissue-specific expression pattern which was essential for proper seed development in rice. The constitutive overexpression led to the interaction of Osr40g3 with OsGF14e in the stamens presumably repressing it which led to pollen sterility. This interaction was, however, highly specific due to the structural distinctiveness of OsGF14e making the phenomenon rice-specific. Nevertheless, in salinity stressed leaves, Osr40g3 interacted with OsEG45 or its ortholog thus leading to salinity tolerance in both rice and Arabidopsis.Competing Interest StatementThe authors have declared no competing interest.