Functional analyses of a novel vesicular membrane protein, TMEM141 during the growth stage in medaka (Oryzias latipes) larvae

ABSTRACT The lantibiotic bacteriocin mutacin II is produced by the group IIStreptococcus mutans. The mutacin II biosynthetic locus consists of seven genes, mutR, -A, -M, -T, -F, -E, and -G, organized as two operons. The mutAMTFEGoperon is transcribed from the mutA promoter 55 bp upstream of the translation start codon for MutA, while the mutRpromoter is 76 bp upstream of the mutR structural gene. Expression of the mutA promoter is regulated by the components of the growth medium, while the mutR promoter activity does not seem to be affected by these conditions. Inactivation of mutR abolishes transcription of the mutAoperon but does not affect its own promoter activity. The expressions of both mutA and mutR promoters are independent of the growth stage, while the production of mutacin II is only elevated at the early stationary phase. Taken together, these results suggest that expression of the mutacin operon is regulated by a complex system involving transcriptional and posttranscriptional or posttranslational controls.

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Transcriptome-wide study in the green microalga Messastrum gracile SE-MC4 identifies prominent roles of photosynthetic integral membrane protein genes during exponential growth stage

Phytochemistry ◽

10.1016/j.phytochem.2021.112936 ◽

2021 ◽

Vol 192 ◽

pp. 112936

Author(s):

C.L. Wan Afifudeen ◽

Ahmad Aziz ◽

Li Lian Wong ◽

Kazutaka Takahashi ◽

Tatsuki Toda ◽

...

Keyword(s):

Membrane Protein ◽

Exponential Growth ◽

Growth Stage ◽

Integral Membrane Protein ◽

Green Microalga

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Insertion of proteins and lipopolysaccharide into the bacterial outer membrane

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2016.0224 ◽

2017 ◽

Vol 372 (1726) ◽

pp. 20160224 ◽

Cited By ~ 19

Author(s):

Istvan Botos ◽

Nicholas Noinaj ◽

Susan K. Buchanan

Keyword(s):

Membrane Protein ◽

Outer Membrane ◽

Protein Complex ◽

Outer Membrane Proteins ◽

Integral Membrane Protein ◽

Membrane Pores ◽

Outer Leaflet ◽

Bam Complex ◽

Bacterial Outer Membrane ◽

Functional Analyses

The bacterial outer membrane contains phospholipids in the inner leaflet and lipopolysaccharide (LPS) in the outer leaflet. Both proteins and LPS must be frequently inserted into the outer membrane to preserve its integrity. The protein complex that inserts LPS into the outer membrane is called LptDE, and consists of an integral membrane protein, LptD, with a separate globular lipoprotein, LptE, inserted in the barrel lumen. The protein complex that inserts newly synthesized outer-membrane proteins (OMPs) into the outer membrane is called the BAM complex, and consists of an integral membrane protein, BamA, plus four lipoproteins, BamB, C, D and E. Recent structural and functional analyses illustrate how these two complexes insert their substrates into the outer membrane by distorting the membrane component (BamA or LptD) to directly access the lipid bilayer. This article is part of the themed issue ‘Membrane pores: from structure and assembly, to medicine and technology’.

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Observations oh Nucleation and Growth of Voids in Nickel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069065 ◽

1970 ◽

Vol 28 ◽

pp. 414-415

Author(s):

J. L. Brimhall ◽

H. E. Kissinger ◽

B. Mastel

Keyword(s):

High Purity ◽

Growth Stage ◽

Elevated Temperatures ◽

Early Growth ◽

Nucleation And Growth ◽

Pure Nickel ◽

Different Temperatures ◽

Total Fluence ◽

Neutron Exposure ◽

Growth Of Voids

Some information on the size and density of voids that develop in several high purity metals and alloys during irradiation with neutrons at elevated temperatures has been reported as a function of irradiation parameters. An area of particular interest is the nucleation and early growth stage of voids. It is the purpose of this paper to describe the microstructure in high purity nickel after irradiation to a very low but constant neutron exposure at three different temperatures.Annealed specimens of 99-997% pure nickel in the form of foils 75μ thick were irradiated in a capsule to a total fluence of 2.2 × 1019 n/cm2 (E > 1.0 MeV). The capsule consisted of three temperature zones maintained by heaters and monitored by thermocouples at 350, 400, and 450°C, respectively. The temperature was automatically dropped to 60°C while the reactor was down.

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Effect of verapamil on cytoplasmic distribution of granules and microfilaments in amphibian urinary bladder

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103681 ◽

1988 ◽

Vol 46 ◽

pp. 324-325

Author(s):

A.J. Mia ◽

L.X. Oakford ◽

T. Yorio

Keyword(s):

Urinary Bladder ◽

Water Flow ◽

Morphological Changes ◽

Granular Cell ◽

Cytosolic Calcium ◽

Calcium Storage ◽

Amphibian Urinary Bladder ◽

Vesicular Membrane ◽

High Concentrations ◽

Cytoskeletal System

The amphibian urinary bladder has been used as a ‘model’ system for studies of the mechanism of action of antidiuretic hormone (ADH) in stimulating transepithelial water flow. The increase in water permeability is accompanied by morphological changes that include the stimulation of apical microvilli, mobilization of microtubules and microfilaments and vesicular membrane fusion events . It has been shown that alterations in the cytosolic calcium concentrations can inhibit ADH transmembrane water flow and induce alterations in the epithelial cell cytomorphology, including the cytoskeletal system . Recently, the subapical granules of the granular cell in the amphibian urinary bladder have been shown to contain high concentrations of calcium, and it was suggested that these cytoplasmic constituents may act as calcium storage sites for intracellular calcium homeostasis. The present study utilizes the calcium antagonist, verapamil, to examine the effect of calcium deprivation on the cytomorphological features of epithelial cells from amphibian urinary bladder, with particular emphasis on subapical granule and microfilament distribution.

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TMCC3 localizes at the three-way junctions for the proper tubular network of the endoplasmic reticulum

Biochemical Journal ◽

10.1042/bcj20190359 ◽

2019 ◽

Vol 476 (21) ◽

pp. 3241-3260

Author(s):

Sindhu Wisesa ◽

Yasunori Yamamoto ◽

Toshiaki Sakisaka

Keyword(s):

Endoplasmic Reticulum ◽

Membrane Proteins ◽

Membrane Protein ◽

Mammalian Cells ◽

Coiled Coil ◽

Transmembrane Domains ◽

Domain Family ◽

Coiled Coil Domain ◽

U2os Cells ◽

Er Membrane

The tubular network of the endoplasmic reticulum (ER) is formed by connecting ER tubules through three-way junctions. Two classes of the conserved ER membrane proteins, atlastins and lunapark, have been shown to reside at the three-way junctions so far and be involved in the generation and stabilization of the three-way junctions. In this study, we report TMCC3 (transmembrane and coiled-coil domain family 3), a member of the TEX28 family, as another ER membrane protein that resides at the three-way junctions in mammalian cells. When the TEX28 family members were transfected into U2OS cells, TMCC3 specifically localized at the three-way junctions in the peripheral ER. TMCC3 bound to atlastins through the C-terminal transmembrane domains. A TMCC3 mutant lacking the N-terminal coiled-coil domain abolished localization to the three-way junctions, suggesting that TMCC3 localized independently of binding to atlastins. TMCC3 knockdown caused a decrease in the number of three-way junctions and expansion of ER sheets, leading to a reduction of the tubular ER network in U2OS cells. The TMCC3 knockdown phenotype was partially rescued by the overexpression of atlastin-2, suggesting that TMCC3 knockdown would decrease the activity of atlastins. These results indicate that TMCC3 localizes at the three-way junctions for the proper tubular ER network.

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