Mutants of the bovine leukemia virus (BLV) transactivator protein (tat, tax, p34, the XLOR gene product) were constructed by site-directed deletions, in-phase linker insertions, or fragment replacements (swapping) among BLV variants. The mutant constructs were transfected into cos cells and transiently expressed. Western blot analysis using a mixture of monoclonal antibodies to wild-type p34 revealed the presence of mutated XLOR gene products in all the mutants tested. The transactivating activity of 11 tax mutants containing site-directed deletions and in-phase linker insertions was completely abolished. Only the swapping mutant tested, a hybrid between two BLV variants, transactivated LTR-directed gene expression at wild-type levels. These data illustrate the narrow range of structural variations that allow full activity of the BLV tax product and suggest that the present molecular structure of the transactivator protein results from heavy evolutionary constraints.
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http://dx.doi.org/10.1016/0042-6822(89)90633-8 | DOI Listing |
Mol Plant Pathol
January 2025
Shanghai Collaborative Innovation Center of Agri-Seeds/State Key Laboratory of Microbial Metabolism, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
Bacterial blight of cotton (BBC) caused by Xanthomonas citri pv. malvacearum (Xcm) is an important and destructive disease affecting cotton plants. Transcription activator-like effectors (TALEs) released by the pathogen regulate cotton resistance to the susceptibility.
View Article and Find Full Text PDFNat Commun
January 2025
Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
Mediator25 (MED25) has been ascribed as a signal-processing and -integrating center that controls jasmonate (JA)-induced and MYC2-dependent transcriptional output. A better understanding of the regulation of MED25 stability will undoubtedly advance our knowledge of the precise regulation of JA signaling-related transcriptional output. Here, we report that Arabidopsis MED16 activates JA-responsive gene expression by promoting MED25 stability.
View Article and Find Full Text PDFNeuroscience
January 2025
Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, China; National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, China; College of Life Science, Shaanxi Normal University, Xi'an, China. Electronic address:
Several studies indicate that fructose can be used as an energy source for subterranean rodents. However, how subterranean rodents utilize fructose metabolism with no apparent physiological drawbacks remains poorly understood. In the present study, we measured field excitatory postsynaptic potentials (fEPSPs) in hippocampal slices from Gansu zokor and SD rats hippocampi before and 60 min after replacement of 10 mM glucose in the artificial cerebrospinal fluid (ACSF) with 10 mM fructose (gassed with 95 % O and 5 % CO).
View Article and Find Full Text PDFCell Mol Gastroenterol Hepatol
January 2025
Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, USA. Electronic address:
Background & Aims: Erythropoietic protoporphyria (EPP) is caused by mutations in ferrochelatase which inserts iron into protoporphyrin-IX (PP-IX) to generate heme. EPP is characterized by PP-IX accumulation, skin photosensitivity, cholestasis, and end-stage liver disease. Despite available drugs that address photosensitivity, treatment of EPP-related liver disease remains an unmet need.
View Article and Find Full Text PDFSci Adv
January 2025
Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA.
Viruses engage in a variety of processes to subvert host defenses and create an environment amenable to replication. Here, using rotavirus as a prototype, we show that calcium conductance out of the endoplasmic reticulum by the virus encoded ion channel, , induces intercellular calcium waves that extend beyond the infected cell and contribute to pathogenesis. Viruses that lack the ability to induce this signaling show diminished viral shedding and attenuated disease in a mouse model of rotavirus diarrhea.
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