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Summary: Cell wall polysaccharide biosynthesis enzymes play important roles in plant growth, development and stress responses. The functions of cell wall polysaccharide synthesis enzymes in plant growth and development have been well studied. In contrast, their roles in plant responses to environmental stress are poorly understood. Previous studies have demonstrated that the rice cell wall cellulose synthase‐like D4 protein (OsCSLD4) is involved in cell wall polysaccharide synthesis and is important for rice growth and development. This study demonstrated that the OsCSLD4 function‐disrupted mutant nd1 was sensitive to salt stress, but insensitive to abscisic acid (ABA). The expression of some ABA synthesis and response genes was repressed in nd1 under both normal and salt stress conditions. Exogenous ABA can restore nd1‐impaired salt stress tolerance. Moreover, overexpression of OsCSLD4 can enhance rice ABA synthesis gene expression, increase ABA content and improve rice salt tolerance, thus implying that OsCSLD4‐regulated rice salt stress tolerance is mediated by ABA synthesis. Additionally, nd1 decreased rice tolerance to osmotic stress, but not ion toxic tolerance. The results from the transcriptome analysis showed that more osmotic stress‐responsive genes were impaired in nd1 than salt stress‐responsive genes, thus indicating that OsCSLD4 is involved in rice salt stress response through an ABA‐induced osmotic response pathway. Intriguingly, the disruption of OsCSLD4 function decreased grain width and weight, while overexpression of OsCSLD4 increased grain width and weight. Taken together, this study demonstrates a novel plant salt stress adaptation mechanism by which crops can coordinate salt stress tolerance and yield. [ABSTRACT FROM AUTHOR]

Aim: To illustrate the method of emergency cerclage with the balloon tamponade and demonstrate the efficacy of this surgery method. Methods: Procedures of the balloon tamponade assisted emergency cerclage were reviewed in detail and outcomes of 39 patients treated with this way were evaluated. Results: From 2017 to 2019, emergency cerclage was successfully performed in 39 patients with a dilated cervix and bulging fetal membranes, assisted by the balloon tamponade. The diameter of the bulging prolapsed membranes ranged from 0.0–10.0 cm, with a median of 2.0 cm. Prolongation of the pregnancy period was from 8 to 138 days, with a median of 29 days. No maternal complications including infections, cervical laceration and cervical bleeding were observed perioperative period. Conclusion: Emergency cerclage is an effective way to prolong gestational period in patients with advanced cervical dilatation and bulging membranes. The balloon tamponade assisted emergency cerclage makes the replacement of fetal membranes back into the uterine cavity easier and effectively, then a successful and convenient emergency cerclage can be performed. [ABSTRACT FROM AUTHOR]

Although Ruminiclostridium josui (formerly Clostridium josui), a strictly anaerobic mesophilic cellulolytic bacterium, is a promising candidate for biomass utilization via consolidated bioprocessing, its host‐vector system has not yet been established. The existence of a restriction and modification system is a significant barrier to the transformation of R. josui. Here, we partially purified restriction endonuclease RjoI from R. josui cell extract using column chromatography. Further characterization showed that RjoI is an isoschizomer of DpnI, recognizing the sequence 5′‐GmetATC‐3′, where the A nucleotide is Dam‐methylated. RjoI cleaved the recognition sequence between the A and T nucleotides, producing blunt ends. We then successfully introduced plasmids prepared from Escherichia coli C2925 (dam−/dcm−) into R. josui by electroporation. The highest transformation efficiency of 6.6 × 103 transformants/μg of DNA was obtained using a square‐wave pulse (750 V, 1 ms). When the R. josui cel48A gene, devoid of the dockerin‐encoding region, cloned into newly developed plasmid pKKM801 was introduced into R. josui, a truncated form of RjCel48A, RjCel48AΔdoc, was detected in the culture supernatant but not in the intracellular fraction. This is the first report on the establishment of fundamental technology for molecular breeding of R. josui. [ABSTRACT FROM AUTHOR]

The biosynthesis of starch is a complex process that depends on the regulatory mechanisms of different functional enzymes, and transcriptional regulation plays an important role in this process. Brittle 1, encoded by BT1, is a transporter of adenosine diphosphate-glucose, which plays an important role in the biosynthesis of starch in the endosperm of cereals. Here, we report that the promoter ( pZmBT1) of the maize BT1 homolog, Zm BT1, contains an MBSI site ( TAACTG), which is important for its activity. Moreover, high expression level of the gene for Zm MYB14 transcription factor was observed in the maize endosperm; its expression pattern was similar to those of the starch synthesis-related genes in maize seeds. Zm MYB14 is a typical 2R- MYB transcription factor localized in the nucleus and possessed transcriptional activation activity. Zm MYB14 could bind to the region of pZmBT1 from −280 to −151 bp and promote its activity through the TAACTG site. It was also observed to promote the activity of pZmSh2, pZmBt2, pZmGBSSI, pZmSSI, and pZmSBE1 in the maize endosperm in transient gene overexpression assays. Furthermore, Zm MYB14 was also shown to bind directly to the promoters of six starch-synthesizing genes, Zm GBSSI, Zm SSI, Zm SSIIa, Zm SBE1, Zm ISA1, and Zm ISA2 in yeast. These findings indicate that Zm MYB14 functions as a key regulator of Zm BT1 and is closely related to the biosynthesis of starch. Our results provide crucial information related to the regulation of starch biosynthesis in maize and would be helpful in devising strategies for modulating starch production in maize endosperm. [ABSTRACT FROM AUTHOR]