Temperature-Sensitive Reaction of a Photosensor Protein YcgF: Possibility of a Role of Temperature Sensor

Biochemistry ◽  
2010 ◽  
Vol 49 (10) ◽  
pp. 2288-2296 ◽  
Author(s):  
Yusuke Nakasone ◽  
Taka-aki Ono ◽  
Asako Ishii ◽  
Shinji Masuda ◽  
Masahide Terazima
Keyword(s):  
Temperature Sensor ◽  
Temperature Sensitive

A High-Speed Temperature Sensor with Low Supply Sensitivity for SoC Thermal Monitoring

2018 ◽  
Vol 27 (07) ◽  
pp. 1850116
Author(s):  
Yuanxin Bao ◽  
Wenyuan Li
Keyword(s):  
Temperature Sensor ◽  
Conversion Rate ◽  
High Speed ◽  
Supply Voltage ◽  
Ring Oscillator ◽  
Temperature Sensitive ◽  
Cmos Process ◽  
Digital Code ◽  
Thermal Monitoring ◽  
Worst Case

A high-speed low-supply-sensitivity temperature sensor is presented for thermal monitoring of system on a chip (SoC). The proposed sensor transforms the temperature to complementary to absolute temperature (CTAT) frequency and then into digital code. A CTAT voltage reference supplies a temperature-sensitive ring oscillator, which enhances temperature sensitivity and conversion rate. To reduce the supply sensitivity, an operational amplifier with a unity gain for power supply is proposed. A frequency-to-digital converter with piecewise linear fitting is used to convert the frequency into the digital code corresponding to temperature and correct nonlinearity. These additional characteristics are distinct from the conventional oscillator-based temperature sensors. The sensor is fabricated in a 180[Formula: see text]nm CMOS process and occupies a small area of 0.048[Formula: see text]mm2 excluding bondpads. After a one-point calibration, the sensor achieves an inaccuracy of [Formula: see text][Formula: see text]1.5[Formula: see text]C from [Formula: see text]45[Formula: see text]C to 85[Formula: see text]C under a supply voltage of 1.4–2.4[Formula: see text]V showing a worst-case supply sensitivity of 0.5[Formula: see text]C/V. The sensor maintains a high conversion rate of 45[Formula: see text]KS/s with a fine resolution of 0.25[Formula: see text]C/LSB, which is suitable for SoC thermal monitoring. Under a supply voltage of 1.8[Formula: see text]V, the maximum energy consumption per conversion is only 7.8[Formula: see text]nJ at [Formula: see text]45[Formula: see text]C.

scholarly journals Role of SpoVA Proteins in Release of Dipicolinic Acid during Germination of Bacillus subtilis Spores Triggered by Dodecylamine or Lysozyme

2006 ◽  
Vol 189 (5) ◽  
pp. 1565-1572 ◽  
Author(s):  
Venkata Ramana Vepachedu ◽  
Peter Setlow
Keyword(s):  
Bacillus Subtilis ◽  
Small Molecules ◽  
Spore Germination ◽  
Dipicolinic Acid ◽  
Temperature Sensitive ◽  
Wild Type ◽  
Ph Optimum ◽  
Inner Membrane ◽  
Temperature Sensitive Mutants

ABSTRACT The release of dipicolinic acid (DPA) during the germination of Bacillus subtilis spores by the cationic surfactant dodecylamine exhibited a pH optimum of ∼9 and a temperature optimum of 60°C. DPA release during dodecylamine germination of B. subtilis spores with fourfold-elevated levels of the SpoVA proteins that have been suggested to be involved in the release of DPA during nutrient germination was about fourfold faster than DPA release during dodecylamine germination of wild-type spores and was inhibited by HgCl2. Spores carrying temperature-sensitive mutants in the spoVA operon were also temperature sensitive in DPA release during dodecylamine germination as well as in lysozyme germination of decoated spores. In addition to DPA, dodecylamine triggered the release of amounts of Ca2+ almost equivalent to those of DPA, and at least one other abundant spore small molecule, glutamic acid, was released in parallel with Ca2+ and DPA. These data indicate that (i) dodecylamine triggers spore germination by opening a channel in the inner membrane for Ca2+-DPA and other small molecules, (ii) this channel is composed at least in part of proteins, and (iii) SpoVA proteins are involved in the release of Ca2+-DPA and other small molecules during spore germination, perhaps by being a part of a channel in the spore's inner membrane.

scholarly journals A High Copy Suppressor Screen Reveals Genetic Interactions Between BET3 and a New Gene: Evidence for a Novel Complex in ER-to-Golgi Transport

Genetics ◽  
1998 ◽  
Vol 149 (2) ◽  
pp. 833-841
Author(s):  
Yu Jiang ◽  
Al Scarpa ◽  
Li Zhang ◽  
Shelly Stone ◽  
Ed Feliciano ◽  
...  
Keyword(s):  
Growth Defect ◽  
Carboxypeptidase Y ◽  
Temperature Sensitive ◽  
Yeast Saccharomyces Cerevisiae ◽  
Specific Suppression ◽  
Golgi Transport ◽  
New Gene ◽  
Insight Into ◽  
Suppressor Screen

Abstract The BET3 gene in the yeast Saccharomyces cerevisiae encodes a 22-kD hydrophilic protein that is required for vesicular transport between the ER and Golgi complex. To gain insight into the role of Bet3p, we screened for genes that suppress the growth defect of the temperature-sensitive bet3 mutant at 34°. This high copy suppressor screen resulted in the isolation of a new gene, called BET5. BET5 encodes an essential 18-kD hydrophilic protein that in high copy allows growth of the bet3-1 mutant, but not other ER accumulating mutants. This strong and specific suppression is consistent with the fact that Bet3p and Bet5p are members of the same complex. Using PCR mutagenesis, we generated a temperature-sensitive mutation in BET5 (bet5-1) that blocks the transport of carboxypeptidase Y to the vacuole and prevents secretion of the yeast pheromone α-factor at 37°. The precursor forms of these proteins that accumulate in this mutant are indicative of a block in membrane traffic between the ER and Golgi apparatus. High copy suppressors of the bet5-1 mutant include several genes whose products are required for ER-to-Golgi transport (BET1, SEC22, USO1 and DSS4) and the maintenance of the Golgi (ANP1). These findings support the hypothesis that Bet5p acts in conjunction with Bet3p to mediate a late stage in ER-to-Golgi transport. The identification of mammalian homologues of Bet3p and Bet5p implies that the Bet3p/Bet5p complex is highly conserved in evolution.

Synaptojanin family members are implicated in endocytic membrane traffic in yeast

1998 ◽  
Vol 111 (22) ◽  
pp. 3347-3356 ◽  
Author(s):  
B. Singer-Kruger ◽  
Y. Nemoto ◽  
L. Daniell ◽  
S. Ferro-Novick ◽  
P. De Camilli
Keyword(s):  
Synaptic Vesicles ◽  
Direct Evidence ◽  
Family Members ◽  
Fluid Phase ◽  
Growth Defect ◽  
Temperature Sensitive ◽  
Close Link ◽  
Fluid Phase Endocytosis ◽  
Synaptojanin 1

The synaptojanins represent a subfamily of inositol 5′-phosphatases that contain an NH2-terminal Sac1p homology domain. A nerve terminal-enriched synaptojanin, synaptojanin 1, was previously proposed to participate in the endocytosis of synaptic vesicles and actin function. The genome of Saccharomyces cerevisiae contains three synaptojanin-like genes (SJL1, SJL2 and SJL3), none of which is essential for growth. We report here that a yeast mutant lacking SJL1 and SJL2 (Deltasjl1 Deltasjl2) exhibits a severe defect in receptor-mediated and fluid-phase endocytosis. A less severe endocytic defect is present in a Deltasjl2 Deltasjl3 mutant, while endocytosis is normal in a Deltasjl1 Deltasjl3 mutant. None of the mutants are impaired in invertase secretion. The severity of the endocytic impairment of the sjl double mutants correlates with the severity of actin and polarity defects. Furthermore, the deletion of SJL1 suppresses the temperature-sensitive growth defect of sac6, a mutant in yeast fimbrin, supporting a role for synaptojanin family members in actin function. These findings provide a first direct evidence for a role of synaptojanin family members in endocytosis and provide further evidence for a close link between endocytosis and actin function.

scholarly journals Postrecruitment Function of Yeast Med6 Protein during the Transcriptional Activation by Mediator Complex

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Gwang Sik Kim ◽  
Young Chul Lee
Keyword(s):  
Gene Expression ◽  
Reporter Gene ◽  
Transcriptional Activation ◽  
Reporter Gene Expression ◽  
Temperature Sensitive ◽  
Internal Deletion ◽  
Cell Extracts ◽  
Evolutionarily Conserved

Med6 protein (Med6p) is a hallmark component of evolutionarily conserved Mediator complexes, and the genuine role of Med6p in Mediator functions remains elusive. For the functional analysis ofSaccharomyces cerevisiaeMed6p (scMed6p), we generated a series of scMed6p mutants harboring a small internal deletion. Genetic analysis of these mutants revealed that three regions (amino acids 33–42 (Δ2), 125–134 (Δ5), and 157–166 (Δ6)) of scMed6p are required for cell viability and are located at highly conserved regions of Med6 homologs. Notably, the Med6p-Δ2 mutant was barely detectable in whole-cell extracts and purified Mediator, suggesting a loss of Mediator association and concurrent rapid degradation. Consistent with this, the recombinant forms of Med6p having these mutations partially (Δ2) restore or fail (Δ5 and Δ6) to restore in vitro transcriptional defects caused by temperature-sensitivemed6mutation. In an artificial recruitment assay, Mediator containing a LexA-fused wild-type Med6p or Med6p-Δ5 was recruited to thelexAoperator region with TBP and activated reporter gene expression. However, the recruitment of Mediator containing LexA-Med6p-Δ6 tolexAoperator region resulted in neither TBP recruitment nor reporter gene expression. This result demonstrates a pivotal role of Med6p in the postrecruitment function of Mediator, which is essential for transcriptional activation by Mediator.

scholarly journals U4 small nuclear RNA dissociates from a yeast spliceosome and does not participate in the subsequent splicing reaction.

1991 ◽  
Vol 11 (11) ◽  
pp. 5571-5577 ◽  
Author(s):  
S L Yean ◽  
R J Lin
Keyword(s):  
Mrna Splicing ◽  
Yeast Cells ◽  
Temperature Sensitive ◽  
Small Nuclear Rna ◽  
Small Nuclear Rnas ◽  
Nuclear Rna ◽  
Sensitive Allele ◽  
U4 Rna ◽  
Small Nuclear Ribonucleoproteins

U4 and U6 small nuclear RNAs reside in a single ribonucleoprotein particle, and both are required for pre-mRNA splicing. The U4/U6 and U5 small nuclear ribonucleoproteins join U1 and U2 on the pre-mRNA during spliceosome assembly. Binding of U4 is then destabilized prior to or concomitant with the 5' cleavage-ligation. In order to test the role of U4 RNA, we isolated a functional spliceosome by using extracts prepared from yeast cells carrying a temperature-sensitive allele of prp2 (rna2). The isolated prp2 delta spliceosome contains U2, U5, U6, and possibly also U1 and can be activated to splice the bound pre-mRNA. U4 RNA does not associate with the isolated spliceosomes and is shown not to be involved in the subsequent cleavage-ligation reactions. These results are consistent with the hypothesis that the role of U4 in pre-mRNA splicing is to deliver U6 to the spliceosome.

scholarly journals U4 small nuclear RNA dissociates from a yeast spliceosome and does not participate in the subsequent splicing reaction

1991 ◽  
Vol 11 (11) ◽  
pp. 5571-5577
Author(s):  
S L Yean ◽  
R J Lin
Keyword(s):  
Mrna Splicing ◽  
Yeast Cells ◽  
Temperature Sensitive ◽  
Small Nuclear Rna ◽  
Small Nuclear Rnas ◽  
Nuclear Rna ◽  
Sensitive Allele ◽  
U4 Rna ◽  
Small Nuclear Ribonucleoproteins

U4 and U6 small nuclear RNAs reside in a single ribonucleoprotein particle, and both are required for pre-mRNA splicing. The U4/U6 and U5 small nuclear ribonucleoproteins join U1 and U2 on the pre-mRNA during spliceosome assembly. Binding of U4 is then destabilized prior to or concomitant with the 5' cleavage-ligation. In order to test the role of U4 RNA, we isolated a functional spliceosome by using extracts prepared from yeast cells carrying a temperature-sensitive allele of prp2 (rna2). The isolated prp2 delta spliceosome contains U2, U5, U6, and possibly also U1 and can be activated to splice the bound pre-mRNA. U4 RNA does not associate with the isolated spliceosomes and is shown not to be involved in the subsequent cleavage-ligation reactions. These results are consistent with the hypothesis that the role of U4 in pre-mRNA splicing is to deliver U6 to the spliceosome.

scholarly journals Mutations affecting the tRNA-splicing endonuclease activity of Saccharomyces cerevisiae.

Genetics ◽  
1988 ◽  
Vol 118 (4) ◽  
pp. 609-617
Author(s):  
M Winey ◽  
M R Culbertson
Keyword(s):  
Growth Defect ◽  
Temperature Sensitive ◽  
Gene Products ◽  
Endonuclease Activity ◽  
Temperature Dependent ◽  
Direct Role ◽  
Trna Splicing

Abstract Two unlinked mutations that alter the enzyme activity of tRNA-splicing endonuclease have been identified in yeast. The sen1-1 mutation, which maps on chromosome 12, causes temperature-sensitive growth, reduced in vitro endonuclease activity, and in vivo accumulation of unspliced pre-tRNAs. The sen2-1 mutation does not confer a detectable growth defect, but causes a temperature-dependent reduction of in vitro endonuclease activity. Pre-tRNAs do not accumulate in sen2-1 strains. The in vitro enzyme activities of sen1-1 and sen2-1 complement in extracts from a heterozygous diploid, but fail to complement in mixed extracts from separate sen1-1 and sen2-1 haploid strains. These results suggest a direct role for SEN gene products in the enzymatic removal of introns from tRNA that is distinct from the role of other products known to affect tRNA splicing.

scholarly journals Yeast Cdc42 functions at a late step in exocytosis, specifically during polarized growth of the emerging bud

2001 ◽  
Vol 155 (4) ◽  
pp. 581-592 ◽  
Author(s):  
Joan E. Adamo ◽  
John J. Moskow ◽  
Amy S. Gladfelter ◽  
Domenic Viterbo ◽  
Daniel J. Lew ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Temperature Sensitive ◽  
Secretory Vesicles ◽  
Polarized Growth ◽  
Vesicle Docking ◽  
Actin Organization ◽  
Late Step ◽  
Rho Family ◽  
Localization Data

The Rho family GTPase Cdc42 is a key regulator of cell polarity and cytoskeletal organization in eukaryotic cells. In yeast, the role of Cdc42 in polarization of cell growth includes polarization of the actin cytoskeleton, which delivers secretory vesicles to growth sites at the plasma membrane. We now describe a novel temperature-sensitive mutant, cdc42-6, that reveals a role for Cdc42 in docking and fusion of secretory vesicles that is independent of its role in actin polarization. cdc42-6 mutants can polarize actin and deliver secretory vesicles to the bud, but fail to fuse those vesicles with the plasma membrane. This defect is manifested only during the early stages of bud formation when growth is most highly polarized, and appears to reflect a requirement for Cdc42 to maintain maximally active exocytic machinery at sites of high vesicle throughput. Extensive genetic interactions between cdc42-6 and mutations in exocytic components support this hypothesis, and indicate a functional overlap with Rho3, which also regulates both actin organization and exocytosis. Localization data suggest that the defect in cdc42-6 cells is not at the level of the localization of the exocytic apparatus. Rather, we suggest that Cdc42 acts as an allosteric regulator of the vesicle docking and fusion apparatus to provide maximal function at sites of polarized growth.

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