Heat-shock protein 104 (Hsp104p) is a protein-remodeling factor that promotes survival after extreme stress by disassembling aggregated proteins and can either promote or prevent the propagation of prions (protein-based genetic elements). Hsp104p can be greatly overexpressed without slowing growth, suggesting tight control of its powerful protein-remodeling activities. We isolated point mutations in Hsp104p that interfere with this control and block cell growth. Each mutant contained alterations in the middle region (MR). Each of the three MR point mutations analyzed in detail had distinct phenotypes. In combination with nucleotide binding site mutations, Hsp104p(T499I) altered bud morphology and caused septin mislocalization, colocalizing with the misplaced septins. Point mutations in the septin Cdc12p suppressed this phenotype, suggesting that it is due to direct Hsp104p-septin interactions. Hsp104p(A503V) did not perturb morphology but stopped cell growth. Remarkably, when expressed transiently, the mutant protein promoted survival after extreme stress as effectively as did wild-type Hsp104p. Hsp104p(A509D) had no deleterious effects on growth or morphology but had a greatly reduced ability to promote thermotolerance. That mutations in an 11-amino acid stretch of the MR have such profound and diverse effects suggests the MR plays a central role in regulating Hsp104p function.
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http://dx.doi.org/10.1091/mbc.e02-08-0502 | DOI Listing |
Nat Commun
January 2025
Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Punjab, India.
Single-point mutations are pivotal in molecular zoology, shaping functions and influencing genetic diversity and evolution. Here we study three such genetic variants of a mechano-responsive protein, cadherin-23, that uphold the structural integrity of the protein, but showcase distinct genotypes and phenotypes. The variants exhibit subtle differences in transient intra-domain interactions, which in turn affect the anti-correlated motions among the constituent β-strands.
View Article and Find Full Text PDFEBioMedicine
January 2025
Department of Chemistry, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, New Cornerstone Science Foundation, Beijing, 100084, China. Electronic address:
Background: The widespread and evolution of RNA viruses, such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), highlights the importance of fast identification of virus subtypes, particularly in non-laboratory settings. Rapid and inexpensive at-home testing of viral nucleic acids with single-base resolution remains a challenge.
Methods: Topologically constrained DNA ring is engineered as substrates for the trans-cleavage of Cas13a to yield an accelerated post isothermal amplification.
Medicina (Kaunas)
January 2025
Department of Surgery, Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania.
In today's world, with its continuing advancements in genetics, the identification of Lynch syndrome (LS) increasingly relies on sophisticated genetic testing techniques. Most guidelines recommend a tailored surveillance program, as well as personalized prophylactic and therapeutic approaches, according to the type of dMMR gene mutation. Carriers of path_MLH1 and path_MSH2 genes have a higher risk of developing colorectal cancer (CRC), despite intensive colonoscopic surveillance.
View Article and Find Full Text PDFAnimals (Basel)
January 2025
Joint International Research Laboratory of Animal Health and Food Safety of Ministry of Education, Single Molecule Biochemistry & Biomedicine Laboratory (Sinmolab), College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
Porcine epidemic diarrhea virus (PEDV) continues to spread globally, causing clinical symptoms in piglets, including watery diarrhea, vomiting, and dehydration. Its exceptionally high morbidity and mortality rate contributes significantly to the economic losses of the swine industry. The continuous genetic mutations of PEDV have compromised the effectiveness of classical strain vaccines.
View Article and Find Full Text PDFBiomedicines
January 2025
Department of Anatomy & Cell Biology, Oklahoma State University Center for Health Sciences, Tulsa, OK 74107, USA.
Speech disorders encompass a complex interplay of neuroanatomical, genetic, and environmental factors affecting individuals' communication ability. This review synthesizes current insights into the neuroanatomy, genetic underpinnings, and environmental influences contributing to speech disorders. Neuroanatomical structures, such as Broca's area, Wernicke's area, the arcuate fasciculus, and basal ganglia, along with their connectivity, play critical roles in speech production, comprehension, and motor coordination.
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