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《Journal of molecular biology》2021,433(19):167162
Many proteins that can assemble into higher order structures termed amyloids can also concentrate into cytoplasmic inclusions via liquid–liquid phase separation. Here, we study the assembly of human Golgi-Associated plant Pathogenesis Related protein 1 (GAPR-1), an amyloidogenic protein of the Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1 proteins (CAP) protein superfamily, into cytosolic inclusions in Saccharomyces cerevisiae. Overexpression of GAPR-1-GFP results in the formation GAPR-1 oligomers and fluorescent inclusions in yeast cytosol. These cytosolic inclusions are dynamic and reversible organelles that gradually increase during time of overexpression and decrease after promoter shut-off. Inclusion formation is, however, a regulated process that is influenced by factors other than protein expression levels. We identified N-myristoylation of GAPR-1 as an important determinant at early stages of inclusion formation. In addition, mutations in the conserved metal-binding site (His54 and His103) enhanced inclusion formation, suggesting that these residues prevent uncontrolled protein sequestration. In agreement with this, we find that addition of Zn2+ metal ions enhances inclusion formation. Furthermore, Zn2+ reduces GAPR-1 protein degradation, which indicates stabilization of GAPR-1 in inclusions. We propose that the properties underlying both the amyloidogenic properties and the reversible sequestration of GAPR-1 into inclusions play a role in the biological function of GAPR-1 and other CAP family members. 相似文献
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David Gutirrez‐Larruscain Santiago Andrs‐Snchez Enrique Rico María Montserrat Martínez‐Ortega 《植物分类学报:英文版》2019,57(1):42-54
Forty-five populations of Pentanema corresponding to seven species included in the Pentanema conyzae clade have been studied using AFLP fingerprinting. The results show that allopolyploidization could have been involved in the diversification of this group, specifically in species P. langeanum and P. maletii. Molecular data confirm the presence of P. britannicum in the Iberian Peninsula and key steps are provided to identify the species that are morphologically the most challenging. 相似文献
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Polyclonal antibodies were prepared against the purified elongation factor Tu (EF-Tu) of Escherichia coli and Bacillus subtilis. Using the methods of Western blotting and microcomplement fixation the cross-reactivities of EF-Tu of 19 different prokaryotes were determined. The immunological distance were compared with the results of 16S rRNA oligonucleotide analysis. An unexpectedly high cross-reactivity was revealed between the EF-Tu of B. subtilis and the antiserum against the EF-Tu of E. coli. A comparison of the predicted amino acid sequences from the tuf-genes of E. coli and B. subtilis yielded two identical peptide fragments that are likely candidates for antibody binding sites.Abbreviations EF-Tu
elongation factor Tu
- GDP
guanosine 5-diphosphate
- GTP
guanosine 5-triphosphate
- MCF
microcomplement fixation
- T
type strain 相似文献
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Total RNA from post mortem human caudate nucleus, cerebellum, cerebral cortex and pheochromocytoma tissues has been prepared. Northern blot analysis, using a single-stranded human proenkephalin A antisense probe (cRNA), revealed the existence of two different proenkephalin A-like sequences in the human caudate nucleus and pheochromocytoma RNA extracts of approximately 1400 and 1000 nucleotides in length respectively, whereas no specific RNA bands could be detected in the cortex and only the 1400 nucleotide band was present in the cerebellum. Under highly stringent hybridization conditions, the proenkephalin A-like RNA bands still appear, indicating that the detected RNA species have either identical or a closely related sequence to that of the wellcharacterized human proenkephalin A mRNA sequence. 相似文献
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Expression of c-myc protooncogene in rat lens cells during development,maturation and reversal of galactose cataracts 总被引:2,自引:0,他引:2
Yi Wen Songtao Shu Nalin J. Unakar Isaac Bekhor 《Molecular and cellular biochemistry》1992,112(1):73-79
It is well established that normal patterns of epithelial cell proliferation and metabolism, and of fiber cell differentiation and maturation are essential for the maintenance of transparency in the ocular lens. Several factors, including exposure to high levels of sugars, have been known to result in the compromise of lens transparency. For example, initiation of lens cell damage by galactose induces lens epithelial cells to proliferate. Elevated levels of c-myc mRNA have usually been correlated with rapid cell growth and increased entry of cells into the S phase. Therefore, changes in c-myc mRNA levels may provide an early indication of the stimulation of lens epithelial cells to proliferate and differentiate, which has been postulated to be an early and important event in response to lens cell injury by galactose. By Northern blot hybridization analysis we quantitated c-myc mRNA levels in the lens capsule epithelia of rats (1) exposed to galactose, and (2) undergoing a partial recovery from the galactose-induced cell damage. At the onset of lens cell damage, we find c-myc mRNA to elevate to 6-fold by 24 hr, and by 48 hr decreases to about 3-fold the normal levels. During recovery, c-myc mRNA continues to be expressed at high levels approaching a 10-fold increase by day 12, then decreasing to levels of about 8-fold the control by day 30. The 24 h transitory elevation in c-myc mRNA in lens epithelial cells is in accord with our previous observations on the 24 h increase in MP26, crystallin and aldose reductase mRNAs following a high influx of galactose. Therefore, the elevation in c-myc mRNA as well suggest that galactose appears to cause lens cells to undergo an early transitory period of gene induction following the exposure of lens cells to galactose. 相似文献
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Kaijiro Anzai Shunsuke Kobayashi Narumi Kitamura Yuri Kanai Hiromichi Nakajima Yoshioki Suehiro Sataro Goto 《Journal of neurochemistry》1986,47(3):673-677
We isolated a mouse genomic clone that hybridized with small RNA present in the cytoplasm of the brain. The RNA was about 150 nucleotides long. This RNA seemed to be specific to the brain, since it was not found in the liver or kidney. The clone DNA contained a sequence homologous to 82-nucleotide "identifier" core sequence of cDNA clones of rat. The sequence contained a split promoter for RNA polymerase III and was flanked by a 12-nucleotide direct repeat (ATAAATAATTTA). 相似文献
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