Hsa_circ_0074032 promotes prostate cancer progression through elevating homeobox A1 expression by serving as a microRNA-198 decoy.

It has been reported that circular RNA hsa_circ_0074032 (circ_0074032) has a higher level in prostate cancer (PCa) tissues. However, the role and regulatory mechanism of circ_0074032 in PCa are still unknown. Circ_0074032 was overexpressed in PCa, and high circ_0074032 level was associated with worse PCa-related prognosis. Functionally, circ_0074032 silencing decreased xenograft tumour growth in vivo and induced cell apoptosis, curbed cell proliferation, migration and invasion in PCa cells in vitro. Furthermore, circ_0074032 was identified as a miR-198 decoy, and miR-198 inhibition abolished circ_0074032 silencing-mediated effects on PCa cell proliferation, apoptosis, migration and invasion. In addition, miR-198 directly targeted homeobox A1 (HOXA1), and HOXA1 weakened miR-198 mimic-mediated impacts on PCa cell malignant phenotypes. Importantly, circ_0074032 regulated HOXA1 expression by sponging miR-198. Our findings uncovered a novel mechanism by which circ_0074032 promoted PCa progression via elevating HOXA1 expression through acting as a miR-198 sponge, providing a mechanism for circ_0074032 to affect the development of PCa.

The polygalacturonase-inhibiting protein 4 (OsPGIP4), a potential component of the qBlsr5a locus, confers resistance to bacterial leaf streak in rice.

MAIN CONCLUSION: OsPGIP4 overexpression enhances resistance to bacterial leaf streak in rice. Polygalacturonase-inhibiting proteins are thought to play important roles in the innate immunity of rice against fungi. Here, we show that the chromosomal location of OsPGIP4 coincides with the major bacterial leaf streak resistance quantitative trait locus qBlsr5a on the short arm of chromosome 5. OsPGIP4 expression was up-regulated upon inoculation with the pathogen Xanthomonas oryzae pv. oryzicola strain RS105. OsPGIP4 overexpression enhanced the resistance of the susceptible rice variety Zhonghua 11 to RS105. In contrast, repressing OsPGIP4 expression resulted in an increase in disease lesions caused by RS105 in Zhonghua 11 and in Acc8558, a qBlsr5a resistance donor. More interestingly, upon inoculation, the activated expression of pathogenesis-related genes was attenuated for those genes involved in the salicylic acid pathway, while the activated expression of jasmonic acid pathway markers was increased in the overexpression lines. Our results not only provide the first report that rice PGIP could enhance resistant against a bacterial pathogen but also indicate that OsPGIP4 is a potential component of the qBlsr5a locus for bacterial leaf streak in rice.

Genomic-associated Markers and comparative Genome Maps of Xanthomonas oryzae pv. oryzae and X. oryzae pv. oryzicola.

Xanthomonas oryzae pv. oryzae (Xoo) and X. oryzae pv. oryzicola (Xoc) cause two major seed quarantine diseases in rice, bacterial blight and bacterial leaf streak, respectively. Xoo and Xoc share high similarity in genomic sequence, which results in hard differentiation of the two pathogens. Genomic-associated Markers and comparative Genome Maps database (GMGM) is an integrated database providing comprehensive information including compared genome maps and full genomic-coverage molecular makers of Xoo and Xoc. This database was established based on bioinformatic analysis of complete sequenced genomes of several X. oryzae pathovars of which the similarity of the genomes was up to 91.39 %. The program was designed with a series of specific PCR primers, including 286 pairs of Xoo dominant markers, 288 pairs of Xoc dominant markers, and 288 pairs of Xoo and Xoc co-dominant markers, which were predicted to distinguish two pathovars. Test on a total of 40 donor pathogen strains using randomly selected 120 pairs of primers demonstrated that over 52.5 % of the primers were efficacious. The GMGM web portal ( http://biodb.sdau.edu.cn/gmgm/ ) will be a powerful tool that can present highly specific diagnostic markers, and it also provides information about comparative genome maps of the two pathogens for future evolution study.