Differential distribution of VGF-derived peptides in the adrenal medulla and evidence for their selective modulation

While vg f gene knockout mice are hyperactive and hypermetabolic, surprisingly the TLQP-21 brain VGF peptide increased energy consumption, suggesting that opposing regulatory effects could be exerted by peptides alternatively cleaved from the VGF precursor. Using antisera to the VGF precursor C-terminus and three cleavage products, we revealed a distinct differential distribution in adrenal, certain peptides (VGF422–430: PGH peptides) being found throughout bovine and swine medulla, while C-terminus and TLQP peptides were confined to adrenaline cells in the above species and in rat and C-terminally shortened forms (VGF604–612: HVLL peptides) to nor-adrenaline cells. Random abattoir samples of bovine and swine adrenal contained 520±40 and 450±60 pmol/g (mean±s.e.m. respectively) of C-terminus peptides and similar or lower amounts of others. Upon gel chromatography, bona fide VGF precursor, ~7.5 and ~3.5 kDa forms were revealed by C-terminus assays, HVLL peptides being limited to small fragments. TLQP peptides included ~7.5 kDa form and peaks accounting for TLQP-21 and predicted TLQP-30 and TLQP-42. Low molecular weight (MW) PGH peptides were revealed, together with a high MW form possibly encompassing the VGF precursor N-terminus. In acutely stressed swine, a striking increase was seen for C-terminus and TLQP peptides, with no significant differences for PGH peptides. A similar response was found in rat TLQP peptides showing a major increase upon an acute swimming stress and 30 min thereafter. A differential processing of the VGF precursor encompassing many areas of its primary sequence and selective modulations of its derived peptides occur in adrenal medullary cells, possibly relevant to adaptive homeostatic responses.

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Selective expression of TLQP-21 and other VGF peptides in gastric neuroendocrine cells and modulation by feeding

Journal of Endocrinology ◽

10.1677/joe-10-0189 ◽

2010 ◽

Vol 207 (3) ◽

pp. 329-341 ◽

Cited By ~ 21

Author(s):

Carla Brancia ◽

Cristina Cocco ◽

Filomena D'Amato ◽

Barbara Noli ◽

Fabrizio Sanna ◽

...

Keyword(s):

Gene Knockout ◽

Cell Types ◽

Neuroendocrine Cells ◽

Mucosal Cell ◽

Clear Cut ◽

Ecl Cell ◽

C Terminus ◽

Gene Knockout Mice ◽

Definition Of ◽

Fasted Rats

Although vgf gene knockout mice are hypermetabolic, administration of the VGF peptide TLQP-21 itself increased energy consumption. Agonist–antagonist roles are thus suggested for different VGF peptides, and the definition of their tissue heterogeneity is mandatory. We studied the rat stomach using antisera to C- or N-terminal sequences of known or predicted VGF peptides in immunohistochemistry and ELISA. TLQP (rat VGF556–565) peptide/s were most abundant (162±11 pmol/g, mean±s.e.m.) and were brightly immunostained in enterochromaffin-like (ECL) cells and somatostatin cells. A peptide co-eluting with TLQP-21 was revealed in HPLC of gastric and hypothalamic extracts, while the extended TLQP-62 form was restricted to the hypothalamus. Novel PGH (rat VGF422–430) peptide/s were revealed in ghrelin cells, mostly corresponding to low MW forms (0.8–1.5 kDa), while VGF C-terminus peptides were confined to neurons. VGF mRNA was present in the above gastric endocrine cell types, and was prominent in chief cells, in parallel with low-intensity staining for further cleaved products from the C-terminal region of VGF (HVLL peptides: VGF605–614). In swine stomach, a comparable profile of VGF peptides was revealed by immunohistochemistry. When fed and fasted rats were studied, a clear-cut, selective decrease on fasting was observed for TLQP peptides only (162±11 vs 74±5.3 pmol/g, fed versus fasted rats, mean±s.e.m., P<0.00001). In conclusion, specific VGF peptides appear to be widely represented in different gastric endocrine and other mucosal cell populations. The selective modulation of TLQP peptides suggests their involvement in peripheral neuro-endocrine mechanisms related to feeding responses and/or ECL cell regulation.

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Study about the Expression of CypA Proteins and Its Blocking Effect in the Cerebellum from FMR1 Gene Knockout Mice by Electroacupuncture of DU1 Acupoint

Rehabilitation Medicine ◽

10.3724/sp.j.1329.2017.05029 ◽

2017 ◽

Vol 27 (5) ◽

pp. 29

Author(s):

Dong LIN ◽

Wanping BU ◽

Xiaoting YANG

Keyword(s):

Knockout Mice ◽

Gene Knockout ◽

Blocking Effect ◽

Fmr1 Gene ◽

Gene Knockout Mice

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Detrimental implication of B1 receptors in myocardial ischemia: evidence from pharmacological blockade and gene knockout mice

International Immunopharmacology ◽

10.1016/s1567-5769(02)00022-x ◽

2002 ◽

Vol 2 (6) ◽

pp. 815-822 ◽

Cited By ~ 47

Author(s):

Caroline Lagneux ◽

Michael Bader ◽

João B. Pesquero ◽

Pierre Demenge ◽

Christophe Ribuot

Keyword(s):

Myocardial Ischemia ◽

Knockout Mice ◽

Gene Knockout ◽

B1 Receptors ◽

Gene Knockout Mice ◽

Pharmacological Blockade

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Enhanced antinociceptive effects of morphine in histamine H2 receptor gene knockout mice

Neuropharmacology ◽

10.1016/j.neuropharm.2006.05.003 ◽

2006 ◽

Vol 51 (3) ◽

pp. 612-622 ◽

Cited By ~ 27

Author(s):

Jalal Izadi Mobarakeh ◽

Kazuhiro Takahashi ◽

Shinobu Sakurada ◽

Atsuo Kuramasu ◽

Kazuhiko Yanai

Keyword(s):

Knockout Mice ◽

Gene Knockout ◽

Receptor Gene ◽

Histamine H2 Receptor ◽

H2 Receptor ◽

Antinociceptive Effects ◽

Gene Knockout Mice

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Increased glycosphingolipid levels in serum and aortae of apolipoprotein E gene knockout mice

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)30162-0 ◽

2002 ◽

Vol 43 (2) ◽

pp. 205-214 ◽

Cited By ~ 3

Author(s):

Brett Garner ◽

David A. Priestman ◽

Roland Stocker ◽

David J. Harvey ◽

Terry D. Butters ◽

...

Keyword(s):

Apolipoprotein E ◽

Knockout Mice ◽

Gene Knockout ◽

E Gene ◽

Apolipoprotein E Gene ◽

Gene Knockout Mice

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The Amino Acids Motif -32GSSYN36- in the Catalytic Domain of E. coli Flavorubredoxin NO Reductase Is Essential for Its Activity

Catalysts ◽

10.3390/catal11080926 ◽

2021 ◽

Vol 11 (8) ◽

pp. 926

Author(s):

Maria C. Martins ◽

Susana F. Fernandes ◽

Bruno A. Salgueiro ◽

Jéssica C. Soares ◽

Célia V. Romão ◽

...

Keyword(s):

Amino Acids ◽

Catalytic Domain ◽

Reductase Activity ◽

Conserved Residues ◽

Mutant Proteins ◽

E Coli ◽

C Terminus ◽

Bona Fide ◽

Oxygen Reductase ◽

Soluble Enzymes

Flavodiiron proteins (FDPs) are a family of modular and soluble enzymes endowed with nitric oxide and/or oxygen reductase activities, producing N2O or H2O, respectively. The FDP from Escherichia coli, which, apart from the two core domains, possesses a rubredoxin-like domain at the C-terminus (therefore named flavorubredoxin (FlRd)), is a bona fide NO reductase, exhibiting O2 reducing activity that is approximately ten times lower than that for NO. Among the flavorubredoxins, there is a strictly conserved amino acids motif, -G[S,T]SYN-, close to the catalytic diiron center. To assess its role in FlRd’s activity, we designed several site-directed mutants, replacing the conserved residues with hydrophobic or anionic ones. The mutants, which maintained the general characteristics of the wild type enzyme, including cofactor content and integrity of the diiron center, revealed a decrease of their oxygen reductase activity, while the NO reductase activity—specifically, its physiological function—was almost completely abolished in some of the mutants. Molecular modeling of the mutant proteins pointed to subtle changes in the predicted structures that resulted in the reduction of the hydration of the regions around the conserved residues, as well as in the elimination of hydrogen bonds, which may affect proton transfer and/or product release.

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The Alopecia Areata Phenotype Is Induced by the Water Avoidance Stress Test In cchcr1-Deficient Mice

Biomedicines ◽

10.3390/biomedicines9070840 ◽

2021 ◽

Vol 9 (7) ◽

pp. 840

Author(s):

Qiaofeng Zhao ◽

Satoshi Koyama ◽

Nagisa Yoshihara ◽

Atsushi Takagi ◽

Etsuko Komiyama ◽

...

Keyword(s):

Alopecia Areata ◽

Gene Knockout ◽

Stress Test ◽

Coiled Coil ◽

Risk Haplotype ◽

Gene Expression Microarray ◽

Wild Type ◽

Gene Knockout Mice ◽

Deficient Mice ◽

Gene Expression Microarray Analysis

We recently discovered a nonsynonymous variant in the coiled-coil alpha-helical rod protein 1 (CCHCR1) gene within the alopecia areata (AA) risk haplotype. We also reported that the engineered mice with this risk allele exhibited. To investigate more about the involvement of the CCHCR1 gene in AA pathogenesis, we developed an AA model using C57BL/6N cchcr1 gene knockout mice. In this study, mice (6–8 weeks) were divided into two groups: cchcr1−/− mice and wild-type (WT) littermates. Both groups were subjected to a water avoidance stress (WAS) test. Eight weeks after the WAS test, 25% of cchcr1−/− mice exhibited non-inflammatory foci of alopecia on the dorsal skin. On the other hand, none of wild-type littermates cause hair loss. The foci resembled human AA in terms of gross morphology, trichoscopic findings and histological findings. Additionally, gene expression microarray analysis of cchcr1−/− mice revealed abnormalities of hair related genes compared to the control. Our results strongly suggest that CCHCR1 is associated with AA pathogenesis and that cchcr1−/− mice are a good model for investigating AA.

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