Ming, F. | Search bioRxiv

bioRxiv2023

OsNAC2 maintains the homeostasis of immune responses to bacterial blight through the OsEREBP1 in rice

Rice bacterial blight, caused by Xanthomonas oryzae pv. Oryzae (Xoo), threatens plant growth and yield. However, the molecular mechanisms underlying rice immunity against Xoo remain elusive. Here, we demonstrated down-regulation of a NAC (NAM-ATAF-CUC) transcription factor OsNAC2 enhanced resistance to bacterial blight disease in rice. Consistently, salicylic acid (SA) biosynthesis was greatly attenuated when OsNAC2 overexpressed. Furthermore, study demonstrated that OsNAC2 can down-regulated the expression of SA synthesis genes, thus mediating SA signal transmission. Simultaneously, OsNAC2 interacted with OsEREBP1 (AP2/ERF family) in the nucleus, may be bloking the inhibition of OsNAC2 to OsICS1, OsPAL3 and so on. Furthermore, OsEREBP1 interacted with OsXb22a in the cytoplasm to exert its positive regulatory effects to bacterial blight. However, OsNAC2-overexpression kept OsEREBP1 in the nucleus and be rapidly degraded in pathogen infection, which adversely affects the interaction of OsEREBP1-OsXb22a. Our results determined that OsNAC2 inhibits the SA signaling and stably interacts with OsEREBP1 to maintain disease resistance. This OsNAC2-OsEREBP1-based homeostatic mechanism provides new insights into rice disease resistance, and it may be useful for improving the disease resistance of important crops through breeding.

molecular biology↗

bioRxiv2021

Fine mapping of goat polledness variant in six Chinese native breeds

BackgroundThe genetic mechanism of goat polledness has been studied for decades, but identifying causative variants and functional genes remains challenging. ResultsUsing a genome-wide association study (GWAS), we identified a significant striking locus for polledness in two different goat breeds. To reduce the linkage disequilibrium among variants for localizing causative variants in the finer region, we sequenced 79 goats from six Chinese native breeds (Jining Gray, Matou, Guizhou black, Yunnan black bone, Chaidamu, and Ujumqin) and identified 483.5 kb CNV (150,334,567-150,818,099) translocated into the previously identified 11.7 kb polled intersex syndrome region, which was consistent with previous research using intersex goat populations. Within the 483.5 kb CNV, a ~322 bp horn-specific element, similar to the superfamily of tRNA-derived families of SINEs, located at the first intron of the ERG gene was identified. The results of the GO enrichment analysis showed that the Horn-SINE element-associated genes were involved in both nervous system and head development. Finally, we used RNA sequencing to investigate gene expression profiles in the horn bud and skin tissues of horned and polled goats. We identified 1077 and 1222 differentially expressed genes between the horn bud and skin tissue in polled and horned goats, respectively. We also identified 367 differentially expressed genes in horn buds between polled and horned animals, and found that the two CNV-related genes, ERG and FOXL2, were upregulated in the horn bud of polled goats. Gene functional enrichment analysis demonstrated that the downregulated genes in the horn bud of polled goats were enriched in skeletal system development, whereas the upregulated genes were significantly overexpressed in muscle tissue development. ConclusionsBroadly, this study describes a novel structural variant responsible for polledness/intersex traits and contributes to the discovery of molecular mechanisms underlying the development and regulation of the polledness trait.

genetics↗