Joint Hypermobility Syndrome and Membrane Proteins: A Comprehensive Review.

Ehlers-Danlos syndromes (EDSs) constitute a heterogeneous group of connective tissue disorders characterized by joint hypermobility, skin hyperextensibility, and tissue fragility. Asymptomatic EDSs, joint hypermobility without associated syndromes, EDSs, and hypermobility spectrum disorders are the commonest phenotypes associated with joint hypermobility. Joint hypermobility syndrome (JHS) is a connective tissue disorder characterized by extreme flexibility of the joints, along with pain and other symptoms. JHS can be a sign of a more serious underlying genetic condition, such as EDS, which affects the cartilage, bone, fat, and blood. The exact cause of JHS could be related to genetic changes in the proteins that add flexibility and strength to the joints, ligaments, and tendons, such as collagen. Membrane proteins are a class of proteins embedded in the cell membrane and play a crucial role in cell signaling, transport, and adhesion. Dysregulated membrane proteins have been implicated in a variety of diseases, including cancer, cardiovascular disease, and neurological disorders; recent studies have suggested that membrane proteins may also play a role in the pathogenesis of JHS. This article presents an exploration of the causative factors contributing to musculoskeletal pain in individuals with hypermobility, based on research findings. It aims to provide an understanding of JHS and its association with membrane proteins, addressing the clinical manifestations, pathogenesis, diagnosis, and management of JHS.

LEA13 and LEA30 Are Involved in Tolerance to Water Stress and Stomata Density in Arabidopsis thaliana.

Late embryogenesis abundant (LEA) proteins are a large protein family that mainly function in protecting cells from abiotic stress, but these proteins are also involved in regulating plant growth and development. In this study, we performed a functional analysis of LEA13 and LEA30 from Arabidopsis thaliana. The results showed that the expression of both genes increased when plants were subjected to drought-stressed conditions. The insertional lines lea13 and lea30 were identified for each gene, and both had a T-DNA element in the regulatory region, which caused the genes to be downregulated. Moreover, lea13 and lea30 were more sensitive to drought stress due to their higher transpiration and stomatal spacing. Microarray analysis of the lea13 background showed that genes involved in hormone signaling, stomatal development, and abiotic stress responses were misregulated. Our results showed that LEA proteins are involved in drought tolerance and participate in stomatal density.

The UMAG_00031 gene from Ustilago maydis encodes a putative membrane protein involved in pH control and morphogenesis.

We report the characterization of the gene UMAG_00031 from Ustilago maydis, previously identified as upregulated at alkaline pH. This gene is located on chromosome 1 and contains an ORF of 1539 bp that encodes a putative protein of 512 amino acids with an MW of 54.8 kDa. The protein is predicted to contain seven transmembrane domains (TMDs) and a signal peptide suggesting that is located in the cell membrane. Null ΔUMAG_00031 mutants were constructed, and their phenotype was analyzed. The mutant displayed a pleiotropic phenotype suggesting its participation in processes of alkaline pH adaptation independent of the Pal/Rim pathway. Also, it was involved in the dimorphic process induced by fatty acids. These results indicate that the protein encoded by the UMAG_00031 gene possibly functions as a receptor of different signals in the cell membrane of the fungus.