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Tea is a healthy beverage made from the leaves of the tea plant [Camellia sinensis (L.) O. Kuntze]. The tea plant is a perennial evergreen plant that is widely distributed in tropical and subtropical regions. PR proteins (pathogenesis-related proteins, PRs) are defense-related proteins induced under pathogenesis-related conditions. Currently, there are a few studies on PRs in plants. Tea leaf color mutants have been of wide interest to scientists as special materials. A tea plant displaying variegated spontaneous albinism found in a local tea plantation in Huangshan City, Anhui Province, China, was used as the material sample in this study. An analysis of preexisting transcriptomic and proteomic data revealed the significant upregulation of three classes of PRs. In order to investigate the correlation between PRs and variegated tea plants, a series of studies were conducted on PR genes. The results revealed the identification of 17 CsPR1, 3 CsPR4 and 31 CsPR5 genes in tea plants using bioinformatics methods, and their structures and promoter sequences. The expression of three PR1, two PR4 and one PR5 genes was determined to be induced in stress treatment experiments involving mechanical damage, insect bites, low temperature treatment, and fungal infections. Additionally, the ribonuclease activity of CsPR4 was successfully verified. This is the first study to report the ribonuclease activity of CsPR4 in tea plants. The results can serve as a reference for future studies on PRs in tea plants, offering new insights into information on albinism in tea plants. [ABSTRACT FROM AUTHOR]

Integrin β4 (ITGB4) is a member of the integrin family, which plays a crucial role in mediating cell adhesion to the extracellular matrix. Recent studies have demonstrated that ITGB4 is involved in tumorigenesis and metastasis during the development of cancer. However, the role of ITGB4 in oral squamous cell carcinoma (OSCC) remains unclear. A Multiplex immunohistochemistry (OPAL™, mIHC) assay was employed to stain ITGB4, ALDH1, PD-L1, cytokeratin (CK), CD8 and PD-1 in a human OSCC tissue microarray, containing 26 normal oral epithelium samples, 21 oral epithelium dysplasia samples and 76 OSCC samples. The expression pattern and clinicopathological characteristics of ITGB4 were analyzed and compared with those of PD-1, PD-L1, ALDH1 and CD8. The correlation between subgroups of tumor cells, including ITGB4+PD-L1+ and ITGB4+ALDH1+, and subgroups of T cells, including CD8+ and CD8+PD-1+, was evaluated using two-tailed Pearson's statistics. A Kaplan–Meier curve was built, and a log-rank test was performed to analyze the survival rate of different subgroups. The mIHC staining results show that ITGB4 was mostly expressed in the tumor cells, with a significant increase in the OSCC specimens compared with normal oral epithelium and oral epithelium dysplasia. The paired analysis, conducted between the OSCC tumor tissue and normal paracancer mucosa, confirmed the results. The study further revealed that ITGB4+PD-L1+ cancer cells, but not ITGB4+ALDH1+ cancer cells, were significantly associated with the infiltration of CD8+ T cells (positivity p = 0.005, positive number p = 0.03). Additionally, ITGB4+PD-L1+ tumor cells were positively correlated with CD8+PD-1+ T cells (positivity p = 0.02, positive number p = 0.03). Most intriguingly, the subgroup of ITGB4/PD-L1high with CD8/PD-1high displayed the best prognosis compared with the other considered subgroups. The results show that the expression of ITGB4 was increased in OSCC compared with normal oral mucosa. Furthermore, a specific subgroup with high levels of expression of ITGB4/PD-L1 and CD8/PD-1 was found to have a relatively better prognosis compared with the other subgroups. Ultimately, this study sheds light on the potential role of ITGB4 in OSCC and provides a basis for further investigation. [ABSTRACT FROM AUTHOR]

Unlike that of other crops, the growth of tea plants can be promoted by aluminum, but its regulation mechanism remains unclear. Some endophytes can also promote growth of plant hosts. In this paper, tea roots treated with aluminum were used to study the growth-promoting traits and aluminum tolerance of endophytes. Meta-16S rDNA analysis revealed that Burkholderia was enriched in tea roots after aluminum treatment, and it was the dominant strain for hydroponic tea roots and field tea roots. Actinomycetes constituted the dominant strains in hydroponic tea seedlings treated with aluminum. Sixteen endophytic bacteria, including 12 strains of Firmicutes , 2 strains of Proteobacteria and 2 strains of Actinomycetes , were isolated and identified from hydroponic tea roots treated with different aluminum concentrations. Growth-promoting activity analysis showed that the isolated endophytic bacteria all had more than one plant growth-promoting trait. Among them, B4 (Bacillus nealsonii), B8 (Brevibacterium frigoritolerans) and A2 (Nocardia nova) bacteria each had three growth-promoting traits. Aluminum tolerance ability analysis indicated that endophyte A1 (Leifsonia shinshuensis) had the strongest aluminum tolerance ability, up to 200 mg l−1 aluminum. Plant–bacteria interactions showed that endophytes A1, A2 and B4 and their synthetic community all had a growth-promoting effect on the growth of wheat lateral roots. Moreover, endophytes A1 and B4 alleviated aluminum stress in wheat. Endophyte A1 also promoted the growth of tea cuttings, especially lateral roots, with/without aluminum. Taken together, aluminum enhanced the distribution of aluminum-tolerant and growth-promoting bacteria, thereby promoting the growth of tea roots. This study provides a new aspect for research on the mechanism by which aluminum promotes tea plant growth. [ABSTRACT FROM AUTHOR]