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Dendrobium catenatum, which grows on the semi humid rocks in the mountains, has been at the top of the ‘Nine Immortals of China’ since ancient times. It is a kind of yin tonic medicine and its main active component is polysaccharide. Cellulose synthase-like D(CslD) genes were predicted to catalyse the biosynthesis of 1,4-β-d-glycan backbone of hemicelluloses, which plays fundamental roles in plant development. To investigate the role of CslD in the development of D. catenatum, eight CslD genes (DcCslD1,2a,2b,3a,3b,4a,4b,5) were identified. The results of protein prediction and analysis showed that CslD2a/2b/4a/4b proteins were acidic proteins. All the proteins had obvious hydrophobic or hydrophilic regions, and had transmembrane structure. Phylogenetic analysis revealed that the DcCslD family could be divided into group I, II, III and IV. DcCslD proteins had a typical Cellulose synthase domain and similar protein structures to the CslDs of other plants. Their promoter regions contain cis regulatory elements related to stress and hormone response. The results of qRT-PCR showed that the identified DcCslDs were differentially expressed in roots, stems and leaves. Most of them were highly expressed in stems and leaves. The environmental stresses examination showed that the expression levels of DcCslD5 were closely associated with drought-recovery treatment; the expression levels of DcCslD1, DcCslD2a, DcCslD2b, DcCslD3a and DcCslD5 were significantly influenced by low temperature. This study systematically analyzed the sequence characteristics of CslD protein of D. catenatum, which can provide reference for further study on the function of CslD protein in the polysaccharide metabolism of D. catenatum. Supplemental data for this article is available online at https://doi.org/10.1080/13102818.2021.1941252 .

Extracellular vesicles (EVs) are special membranous structures released by almost every cell type that carry and protect some biomolecules from being degraded. They transport important signaling molecules involved in cell communication, migration, and numerous physiological processes. EVs can be categorized into two main types according to their size: i) small extracellular vesicles (sEVs), such as exosomes (30–150 nm), released from the fusion of multivesicular bodies (MVBs) with the plasma membrane, and ii) large EVs, such as microvesicles (100–1000 nm). These are no longer considered a waste product of cells, but regulators of intercellular communication, as they can transport specific repertoires of cargos, such as proteins, lipids, and nucleic acids to receptor cells to achieve cell-to-cell communication. This indicates the existence of different mechanisms, which controls the cargos sorting into EVs. This review mainly gives a description about the biological roles of the cargo and the sorting mechanisms of sEVs, especially exosomes.

Alkaline/neutral invertase (NI) proteins irreversibly break down sucrose into glucose and fructose and play a vital role in carbohydrate and plant growth and development. Currently, a comprehensive understanding of NI genes in Dendrobium catenatum is lacking. After genome-wide identification and prediction, nine DcNI genes were identified and named DcNI1–DcNI9. Through comprehensive analysis of gene structure, amino acid sequence, conserved motif and phylogenetic tree, it was found that the DcNI gene family has a typical conserved region and its amino acid sequence is similar to other plant NI genes. However, DcNI3 lost amino acid sequences at both the N-terminus and C-terminus, while DcNI8 lost amino acids at the C-terminus. Phylogenetic analysis revealed that the DcNI family could be divided into α and β groups. It reveals conservation and divergence of DcNIs. Predictive analysis of cis-acting elements in the promoter region reveals the potential response of DcNI protein to hormones and environmental stress and suggests it to be widely involved in growth and development. DcNIs were differentially expressed in different tissues such as roots, stems and leaves. In particular, DcNI4 was highly expressed in the stem. They also had a differential expression response under drought, cold, P1 fungus infection and jasmonic acid (JA) treatment. To the best of our knowledge, this is the first genome-wide analysis of the DcNI gene family in D. catenatum. This study will provide important and primary information for the functional study of the DcNI gene family and the polysaccharide synthesis pathway in D. catenatum.

Anthracnose, caused by Colletotrichum gloeosporioides, is highly harmful for walnut production in the world. To better control this disease, the inhibitory effects of 3 fungicides against Colletotrichum gloeosporioides were determined, and the results showed that prochloraz had better inhibitory activity. Through comparative metabolomics analysis, 311 metabolites might be associated with the walnut peel response to Colletotrichum gloeosporioides under prochloraz treatment. Furthermore, we supposed that the phenylpropanoid pathway might be induced by prochloraz to resist Colletotrichum gloeosporioides infection. In conclusion, the upregulated metabolites in the phenylpropanoid pathway might be related to synthesize lignin to further form a cell wall against Colletotrichum gloeosporioides infection.

It has been reported that autophagic stress, which is involved in many diseases, plays a key role in the development of diabetic nephropathy (DN). In this study, we investigated the effects of high dose vitamin E on renal tubular epithelial cells and autophagic stress-related mechanisms in diabetes condition. In diabetic rats, high dose vitamin E treatment significantly decreased the serum creatinine, urea nitrogen, urinary albumin and urinary protein, reduced the levels of LCN2, HAVCR1, LDH and 8-OHdG in urine, and attenuated the cellular apoptosis and interstitial fibrosis in renal cortex. In vitro, vitamin E could reduce the release of LCN2 and HAVCR1 and the protein levels of caspase 3 and TGF-β1, as well as improve the growth inhibition in cultured HK-2 cells after exposure to advanced glycation end products (AGEs). Also, LC3-II and SQSTM1-positive dots were significantly increased in the renal tubular epithelial cells of DN patients and diabetic rats, and in HK-2 cells after exposure to AGEs, which were markedly declined by vitamin E. In addition, we found that the autophagosome formation was not affected by AGEs, as assessed by the mRNA levels of LC3B, Beclin-1, and ATG7. However, AGEs blocked the lysosomal degradation of autophagosome, which was characterized by a decrease in the enzymatic activity of cathepsin B/cathepsin L and DQ-ovalbumin degradation in HK-2 cells, indicating that AGEs-induced accumulation of autophagic vacuoles was a sign of autophagic stress. Interestingly, vitamin E exerted a protective effect on lysosomes to reduce the autophagic stress. Taken together, we conclude that autophagic stress may play an important part in the progression of DN, and alleviation of autophagic stress though improvement of lysosomal function provides a promising novel approach for treating DN.

Histone lysine methylation, controlled by the SET Domain Group (SDG) gene family, is part of the histone code that regulates chromatin function and epigenetic control of gene expression. Analyzing the SDG gene family in Brassica rapa for their gene structure, domain architecture, subcellular localization, rate of molecular evolution and gene expression pattern revealed common occurrences of subfunctionalization and neofunctionalization in BrSDGs. In comparison with Arabidopsis thaliana, the BrSDG gene family was found to be more divergent than AtSDGs, which might partly explain the rich variety of morphotypes in B. rapa. In addition, a new evolutionary pattern of the four main groups of SDGs was presented, in which the Trx group and the SUVR subgroup evolved faster than the E(z), Ash groups and the SUVH subgroup. These differences in evolutionary rate among the four main groups of SDGs are perhaps due to the complexity and variability of the regions that bind with biomacromolecules, which guide SDGs to their target loci.

Background The previous study showed that the cardiac arrhythmias induced by myocardial ischemia and reperfusion were attenuated by the pretreatment of acupuncture; however, the related mechanism is not understood. The present study was therefore designed to determine whether intracellular Ca2+ ([Ca2+]i) and connexin 43 (Cx43) are involved in the mediation of the anti-arrhythmic effect of electro-acupuncture (EA) pretreatment in the rats subjected to simulative global ischemia and reperfusion (SGIR). Methods SGIR was made in the isolated heart by a low flow perfusion followed by a flow restoration. Four groups of animals are involved in the present study, including normal control group, SGIR group, EA group and EA plus 18 beta-glycyrrhetinic acid (EAG) group. For EA pretreatment, bilateral Neiguan acupoints (PC6) of the rats were stimulated for 30 min once a day in 3 consecutive days. Cx43 antagonist was given to the rats in EAG group 30 minutes before the EA pretreatment. The resting [Ca2+]i concentration, calcium oscillation, the contents of total Cx43 and non-phosphrylated Cx43 and arrhythmia score were compared among different groups. Results In EA group, the arrhythmic score, the resting [Ca2+]i concentration and the number of [Ca2+]i oscillations were all significantly less than those in SGIR group (all P