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As one of the most common pathological changes in trauma and surgery practice, intestinal ischemia-reperfusion (I/R) injury is regarded as a major precipitating factor in the occurrence and development of fatal diseases. BRCA1–BRCA2-containing complex subunit 36 (BRCC36), a deubiquitinase, has been proved important in a variety of pathophysiological processes such as DNA repair, cell cycle regulation, tumorigenesis, and inflammatory response. However, the effect of BRCC36 on intestinal mucosal barrier injury after I/R has not been fully elucidated. Our research found that BRCC36 aggravated intestinal mucosal barrier injury caused by bone morphogenetic protein 2 after I/R by downregulating peroxisome proliferator-activated receptor-γ (PPARγ) signaling. These results suggested that BRCC36/PPARγ axis might serve as a potential therapeutic target for preventing intestinal mucosal barrier injury after I/R.

Somatic embryogenesis (SE) plays a vital role in genetic transformation and massive propagation of important agronomical and economical crops. Here, we conducted a systematic assessment of the morphological, cytochemical, and cytogenetical characteristics of six culture strains with various embryogenic/regenerative potential during SE process in cotton. Results indicated that the six cell culture strains had stable ploidy levels, and did not reveal any relationship between the cytogenetic state and their morphogenetic potential. Moreover, the six culture strains were compared via double staining with Evans blue and Acetocarmine to efficiently distinguish embryogenic and non-embryogenic cells and determine the embryogenic nature of the calli. In addition, the kind of auxins added in medium affected not only growth property, color, size of cell clumps but also ploidy level and regeneration ability. By combining analysis of morphological, cytochemical, and cytogenetical characteristics of the cell cultures, we are able to obtain and maintain homogeneous cell population with high morphogenic and regeneration ability and establish efficient somatic embryogenesis and regeneration system from short-term cell cultures in upland cotton, which highlight the application of biotechnological approaches in crop breeding, and above all, to better understand totipotency of cells in higher plants.

To get a broader view on the molecular mechanisms underlying somatic embryogenesis (SE) in cotton (Gossypium hirsutum L.), global analysis of cotton transcriptome dynamics during SE in different sister lines was performed using RNA-Seq. A total of 204 349 unigenes were detected by de novo assembly of the 214 977 462 Illumina reads. The quantitative reverse transcription–polymerase chain reaction (qRT-PCR) measurements were positively correlated with the RNA-Seq results for almost all the tested genes (R2 = 0.841, correlation was significant at the 0.01 level). Different phytohormone (auxin and cytokinin) concentration ratios in medium and the endogenous content changes of these two phytohormones at two stages in different sister lines suggested the roles of auxin and cytokinin during cotton SE. On the basis of global gene regulation of phytohormone-related genes, numerous genes from all the differentially expressed transcripts were involved in auxin and cytokinin biosynthesis and signal transduction pathways. Analyses of differentially expressed genes that were involved in these pathways revealed the substantial changes in gene type and abundance between two sister lines. Isolation, cloning and silencing/overexpressing the genes that revealed remarkable up- or down-expression during cotton SE were important. Furthermore, auxin and cytokinin play a primary role in SE, but potential cross-talk with each other or other factors remains unclear.

Arabinogalactan proteins (AGPs) are involved in many aspects of plant development. In this study, biochemical and genetic approaches demonstrated that AGPs are abundant in developing fibers and may be involved in fiber initiation and elongation. To further investigate the role of AGPs during fiber development, a fasciclin-like arabinogalactan protein gene (GhFLA1) was identified in cotton (Gossypium hirsutum). Overexpression of GhFLA1 in cotton promoted fiber elongation, leading to an increase in fiber length. In contrast, suppression of GhFLA1 expression in cotton slowed down fiber initiation and elongation. As a result, the mature fibers of the transgenic plants were significantly shorter than those of the wild type. In addition, expression levels of GhFLAs and the genes related to primary cell wall biosynthesis were remarkably enhanced in the GhFLA1 overexpression transgenic fibers, whereas the transcripts of these genes were dramatically reduced in the fibers of GhFLA1 RNA interference plants. An immunostaining assay indicated that both AGP composition and primary cell wall composition were changed in the transgenic fibers. The levels of glucose, arabinose, and galactose were also altered in the primary cell wall of the transgenic fibers compared with those of the wild type. Together, our results suggested that GhFLA1 may function in fiber initiation and elongation by affecting AGP composition and the integrity of the primary cell wall matrix.

Dirigent super-family abounds throughout the plant kingdom, especially vascular plants. To elucidate the function of cotton (Gossypium hirsutum) DIR genes in lignification, two cDNAs (designated GhDIR1 and GhDIR2) encoding putative dirigent proteins were isolated from cotton cDNA libraries. Real-time quantitative reverse transcription-polymerase chain reaction analysis revealed that GhDIR1 transcript was preferentially accumulated in cotton hypocotyls, whereas GhDIR2 was predominantly expressed in cotton fibers. Overexpression of GhDIR1 gene resulted in an increase in lignin content in transgenic cotton plants, compared with that of wild type. Histochemical assay revealed that the transgenic plants displayed more widespread lignification than that of wild type in epidermis and vascular bundle. Furthermore, the transgenic cotton plants displayed more tolerance to the infection of Verticillium dahliae. Our data suggest that GhDIR1 may be involved in cotton lignification which can block the spread of fungal pathogen V. dahliae.

Over the past few decades genetic engineering has been applied to improve cotton breeding. Agrobacterium medicated transformation is nowadays widely used as an efficient approach to introduce exogenous genes into cotton for genetically modified organisms. However, it still needs to be improved for better transformation efficiency and higher embryogenic callus induction ratios. To research further the difference of mechanisms for morphogenesis between embryogenic callus and non-embryogenic callus, we carried out a systematical study on the histological and cellular ultrastructure of Agrobacterium transformed calli. Results showed that the embryogenic callus developed nodule-like structures, which were formed by small, tightly packed, hemispherical cells. The surface of some embryogenic callus was covered with a fibrilar-like structure named extracellular matrix. The cells of embryogenic calli had similar morphological characteristics. Organelles of embryogenic callus cells were located near the nucleus, and chloroplasts degraded to proplastid-like structures with some starch grains. In contrast, the non-embryogenic calli were covered by oval or sphere cells or small clusters of cells. It was observed that cells had vacuolation of cytoplasm and plastids with a well organized endomembrane system. This study aims to understand the mechanisms of embryogenic callus morphogenesis and to improve the efficiency of cotton transformation in future.

Behcet's disease (BD) accompanied by intestinal involvement is called intestinal BD. Although recent studies have attained positive feedback with the administration of anti-TNF-α agents in patients with BD, only a few reports on the study of etanercept in intestinal BD have been found. In this study, 35 cases of intestinal BD were treated with conventional therapy (prednisone or methotrexate) for a minimum period of 3 months (group 1). Another 19 patients who failed to respond to conventional therapy were then treated with etanercept (25 mg twice a week for 3 months). During each subsequent relapse, the patients were given the same treatment. The main outcome measures were the four criteria for diagnosis of BD (buccal ulcers, genital ulcers, ocular lesions, and skin lesions), the manifestation of intestinal involvement (abdominal symptoms, double-balloon enteroscopy), laboratory examinations of the acute phase reactants (erythrocyte sedimentation rate) and C-reactive protein, and relapses. As a result of the administered therapy, the healing rate of buccal and genital ulcers, the remission rate of ocular lesions, skin lesions, and abdominal symptoms, the healing rate of intestinal ulcers, and the recovery rate of ESR and CRP were significantly higher in group 2 than those of group 1. The relapse rate in the etanercept therapy was reduced significantly when compared with conventional therapy group. In conclusion, etanercept treatment, in contrast to the conventional therapy, can result in better curative effect and less adverse reactions in intestinal BD.