Functional analysis of RF2a, a rice transcription factor

RF2a is a bZIP transcription factor that regulates expression of the promoter of rice tungro bacilliform bad-navirus. RF2a is predicted to include three domains that contribute to its function. The results of transient assays with mutants of RF2a from which one or more domains were removed demonstrated that the acidic domain was essential for the activation of gene expression, although the proline-rich and glutamine-rich domains each played a role in this function. Studies using fusion proteins of different functional domains of RF2a with the 2C7 synthetic zinc finger DNA-binding domain showed that the acidic region is a relatively strong activation domain, the function of which is dependent on the context in which the domain is placed. Data from transgenic plants further supported the conclusion that the acidic domain was important for maintaining the biological function of RF2a. RF2a and TBP (TATA-binding protein) synergistically activate transcription in vitro (Zhu, Q., Ordiz, M. I., Dabi, T., Beachy, R. N., and Lamb, C. (2002) Plant Cell 14, 795-803). In vitro and in vivo assays showed that RF2a interacts with TBP through the glutamine-rich domain but not the acidic domain. Functional analysis of such interactions indicates that the acidic domain activates transcription through mechanisms other than via the direct recruitment of TBP.Fil: Dai, Shunhong. Chinese Academy of Sciences; República de China. Donald Danforth Plant Science Center; Estados UnidosFil: Petruccelli, Silvana. Donald Danforth Plant Science Center; Estados Unidos. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Ordiz, Maria Isabel. Donald Danforth Plant Science Center; Estados UnidosFil: Zhang, Zhihong. Donald Danforth Plant Science Center; Estados UnidosFil: Chen, Shouyi. Chinese Academy of Sciences; República de ChinaFil: Beachy, Roger N.. Donald Danforth Plant Science Center; Estados Unido

An improved method of searching inferior parathyroid gland for the patients with papillary thyroid carcinoma based on a retrospective study

ObjectiveMany surgeons knew the importance of parathyroid gland (PG) in the thyroid surgery, but it was even more difficult to be protected. This study aimed at evaluating the effectiveness of the improved method of searching inferior parathyroid gland (IPG).Methods213 patients were enrolled and divided into test and control groups according to different methods of searching IPG in the surgery. Consequently, we compared the surgical outcome parameters between the two groups, including the operative time, numbers of PG identifying (PG protection in situ, PG auto-transplantation, and PG accidental removal), numbers of the total lymph node (LN) and metastatic LN, parathyroid hormone (PTH), transient hypoparathyroidism, transient recurrent laryngeal nerve palsy, and postoperative bleeding.ResultsWe identified 194 (194/196, 98.98%) and 215 (215/230, 93.48%) PGs in the test group and control group, respectively, and there was a significant difference (P = 0.005), and this result was due to IPG identification differences (96/98, 97.96% vs. 100/115, 86.96%, P = 0.004). Meanwhile, there was a lower ratio of IPG auto-transplantation in the test group compared with that in the control group (46.94% vs. 64.35%, P = 0.013). Serum PTH one day after the operation was 3.65 ± 1.86 vs. 2.96 ± 1.64 (P = 0.043) but with no difference at 6 months. There were no differences in metastatic LN and recurrent laryngeal nerve palsy between two groups.ConclusionThe improved method of searching IPG was simple, efficient, and safe, which was easy to be implemented for searching IPG and protecting it well

Pleiotropic effects of the twin-arginine translocation system on biofilm formation, colonization, and virulence in Vibrio cholerae

<p>Abstract</p> <p>Background</p> <p>The Twin-arginine translocation (Tat) system serves to translocate folded proteins, including periplasmic enzymes that bind redox cofactors in bacteria. The Tat system is also a determinant of virulence in some pathogenic bacteria, related to pleiotropic effects including growth, motility, and the secretion of some virulent factors. The contribution of the Tat pathway to <it>Vibrio cholerae </it>has not been explored. Here we investigated the functionality of the Tat system in <it>V. cholerae</it>, the etiologic agent of cholera.</p> <p>Results</p> <p>In <it>V. cholerae</it>, the <it>tatABC </it>genes function in the translocation of TMAO reductase. Deletion of the <it>tatABC </it>genes led to a significant decrease in biofilm formation, the ability to attach to HT-29 cells, and the ability to colonize suckling mouse intestines. In addition, we observed a reduction in the output of cholera toxin, which may be due to the decreased transcription level of the toxin gene in <it>tatABC </it>mutants, suggesting an indirect effect of the mutation on toxin production. No obvious differences in flagellum biosynthesis and motility were found between the <it>tatABC </it>mutant and the parental strain, showing a variable effect of Tat in different bacteria.</p> <p>Conclusion</p> <p>The Tat system contributes to the survival of <it>V. cholerae </it>in the environment and <it>in vivo</it>, and it may be associated with its virulence.</p