• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1392-1396
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• 2005

Proteolytic digestion and CD measurement of wild-type and mutant cyclic AMP receptor proteins (CRPs) were performed either in the presence or absence of cyclic nucleotide. Results indicated that transition of a structural change to the hinge region by the binding of cAMP to the anti site was required for the binding of cAMP to the syn site near the hinge region and, although the occupancy of cAMP in the anti site increased the protein stability, CRP adopted more a stable conformation by the binding of cAMP to the syn site.

• Journal of Life Science
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• v.13 no.5
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• pp.746-750
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• 2003

Lactose operon contains two CRP binding sites at promoter(CRP1 site) and operator(CRP2 site) regions at lac operon. CRP protein can bind to both sites with the different binding affinity. CRP1 site, major CRP binding site, acts the transcription activation with the fully unknown mechanism by binding of CRP. In this study, the binding affinities of CRP1 site and CRP2 site were measured with the fluorescein-labeled oligomers, which contain CRP1 site and the three different spacing sequences between GTGA and TCAC at CRP2 site. Results showed that CRP:cAMP complex bound to CRP1 site 3 times more strongly than CRP2 site and the base spacing between GTGA and TCAC was not the only factor to affect the binding affinity of CRP to CRP2 site.

• Journal of Life Science
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• v.13 no.5
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• pp.751-755
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• 2003

Cyclic AMP receptor proteins(CRP) activate many genes in Escherichia coli by binding of cAMP with not fully known mechanism. CRP existed as apo-CRP in the absence of cAMP, $CRP;(cAMP)_2$$_2$ at low(micromolar) cAMP concentration, or $CRP;(cAMP)_4$ at high(millimolar) concentration of cAMP. This study is designed to measure the thermal stability of S83G CRP, which substituted glycine for serine at amino acid 83 position, with CD spectrapolarimeter at 222nm by the constant elevation of temperature from $20^{\circ]C\; to\; 90^{\circ}C\; at\; 1^{\circ}C/min$. The non-linear regression analysis showed that melting temperatures were 68.4, 72.0, and $82.3^{\circ}C$ for no cAMP, 0.1mM cAMP, and 5mM cAMP, respectively. Result showed the strong thermal stability of CRP by binding of additional cAMP molecules to region between the hinge region and helix-turn-helix(HTH) motif at 5mM cAMP concentration.

• Development and Reproduction
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• v.22 no.1
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• pp.65-72
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• 2018

Cyclic AMP-response element binding protein zhangfei (CREBZF), a member of ATF/CREB (activating transcription factor/ cAMP response element binding protein) family, regulates numerous cellular functions and development of cells by interacting transcription factors. This study discovered the expression pattern of CREBZF in seminiferous tubule of testes during the postnatal development of mice. In testis, CREBZF mRNA expression was the highest among other organs. Immunofluorescence analyses showed that the CREBZF was specifically expressed on spermatocyte but not in spermatogonia and Sertoli cells in seminiferous epithelium of mouse testis. Semi-quantitative polymerase chain reaction (PCR) analysis showed that CREBZF transcript level was significantly elevated during postnatal development of mouse testis. Confocal imaging analysis indicated that the protein expression of CREBZF in seminiferous tubule remained low until postnatal day (PD) 14, and was dramatically increased in PD 21. Interestingly, only one type of the spermatocyte expressed CREBZF specifically among SCP3-positive spermatocytes. Taken together, these results suggest that CREBZF may be novel putative marker of the spermatocyte and regulate meiosis during postnatal development of mice.

• Development and Reproduction
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• v.22 no.1
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• pp.95-104
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• 2018

CREBZF (cAMP-response element binding protein zhangfei) is a member of ATF/CREB family, and which regulates various cellular functions by suppressing major factors with direct interaction. In this study, we have examined the expression of CREBZF on mouse endometrium during uterus estrous cycles and estrogen (E2) treatment. In uterus, CREBZF mRNA expression was higher than other organs and mRNA and protein of CREBZF was increased in proestrus phase and decreased in estrus phase. The expression of CREBZF in 3-weeks old mouse uterus was reduced by E2 injection in endometrium. In addition, the expression of progesterone receptor, a marker of E2 in ovariectomized mice was found to be strongly expressed in stroma, while CREBZF was only expressed in epithelium. Also, we conformed that E2-suppressed CREBZF was restored by co-injection of ICI 182,780, an estrogen receptor antagonist. Overall, these results suggest that CREBZF is regulated by estrogen and involved in ER signaling pathway in mouse uterus.

• The Korean Journal of Zoology
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• v.37 no.1
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• pp.40-48
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• 1994

세포분화에 따른 Small GTP-binding protein의 역할을 밝히기 위하여 Retinoic acid(RA)와 dibutyryl cyclic AMP(dbcAMP)로 분화를 유도한 F9 기형암종세포의 형태적인 변화와 함께 Small GTP-binding protein의 분포를 조사하였다. RA와 dbcAMP를 처리한 세포는 분화유도 5일경(초기 분화 단계)에 분명한 세포의 경계를 보이기 시작하여 7일경(분화 후기 단계)에는 거의 모든 세포가 등근 분화된 형태로 전환되었다. 이 분화과정 동안 세포막에는 많은 microvilli와 lamellopodia 같은 구조물이 나타났다. 아울러 초기 분화 단계에 많은 량의 laminin이 발현되었으며 분화 후기에 microtubule의 재분포가 관찰되었다. 세종류의 Small GTP-binding protein(25 23, 21 KD)이 F9 세포의 막성분과 세포질에서 관찰되었으며 분화가 진행됨에 따라서 세단백질 모두 증가되는 양상을 보였다 이러한 결과는 Small GTP-binding protein이 F9 세포의 분화에 특별한 기능을 가지고 있음을 시사해 주고 있다.

• Journal of Life Science
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• v.14 no.2
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• pp.309-314
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• 2004

Cyclic AMP receptor protein (CRP) is involved in the transcriptional regulation of more than 100 genes in E. coli. CRP dimer is converted into active form via the sequential conformation change of cAMP binding pocket, hinge region and HTH DNA binding motif by binding of cAMP. The temperature gradient gel electrophoresis (TGGE) was applied to CRP protein to know whether it was an efficient technique to study the conformational transitions and the thermal stability. TGGE showed the unfolding process of wild-type and S83G CRP proteins with the temperature gradient set from 29 to 71$^{\circ}C$ on nondenaturing polyacrylamide gel. Melting temperature (Tm) was 57$\pm$1 and 55$\pm$1$^{\circ}C$ for wild-type and S83G CRP, respectively in acidic buffer[89.8 mM Glycine and 24 mM Boric acid (pH 5.8)].

• BMB Reports
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• v.30 no.5
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• pp.320-325
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• 1997

Thioredoxin is a multi-functional protein which is ubiquitous in microorganisms, animals and plants. Previously, expression of the E. coli thioredoxin gene was found to be negatively regulated by cAMP. In the present study, the effect of cAMP on two separate promoters of the E. coli thioredoxin gene was investigated. Cyclic AMP had a repressible effect on P1 and P1P2 promoter activity of the constructs. This effect was also observed in the cya strain. The P2 promoter construct gave very high -galactosidase activity, and its expression was not affected by exogenous cAMP. It was assumed that a cis-acting negative element, probably the cAMP-CRP binding site, might have been deleted in the P1 promoter construct. Repression of the thioredoxin gene expression by cAMP appeared to be independent of ppGpp.

• The Korean Journal of Pharmacology
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• v.31 no.2
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• pp.219-231
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• 1995

Vasoactive intestinal polypeptide(VIP) and ${\beta}-adrenergic$ agonists have immunomodultory effects on the peripheral blood T-lymphocytes of rat through their own receptors. Both of them utilize the same signal transduction pathway. That is, the stimulatory guanine nucleotide binding protein(G protein) mediates the receptor-adenylyl cyclase coupling, producing intracellular increase of cyclic adenosine monophosphate(cAMP). In the previous experiment, propranolol, a ${\beta}-adrenergic$ receptor blocker, inhibited the VIP-induced protein phosphorylation in lymphocytes. However, propranolol could not block the effect induced by forskolin. Therefore, this study was designed to elucidate the mechanism of the inhibitory action of propranolol on the effects of VIP. Using peripheral blood lymphocytes of rats, the effect of propranolol on the receptor binding characteristics of VIP was observed. And the effects of propranolol were compared to the effects of timolol on the cAMP increase induced by isoproterenol, VIP or forskolin. The results obtained are as follows. 1) Receptor binding study showed no significant differences in the affinity or density of VIP receptor between the control and propranolol-pretreated groups. 2) VIP-induced increase of cAMP was inhibited by propranolol, but not by timolol. 3) Both propranolol and timolol suppressed the isoproterenol-induced cAMP increase. 4) Propranolol also inhibited the histamine-induced cAMP increase. 5) Propranolol did not inhibit the increase of cAMP stimulated by forskolin. 6) Lidocaine did not block the VIP-induced cAMP increase. These results show that the inhibitory mechanism of propranolol is not related to ${\beta}-adrenergic$ receptor or its membrane stabilizing effect, and it is suggested that propranolol can block the effects of VIP by inhibiting the intermediate step between the VIP receptor and adenylyl cyclase.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.104-104
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• 2022

Dendropanax morbiferus H. Lev has been reported to have some pharmacologic activities and also interested in functional cosmetics. We found that the water extract of D. morbiferus leaves significantly inhibited tyrosinase activity and melanin formation in α-melanocyte stimulating hormone (MSH)-induced B16-F10 cells. D. morbiferus reduced melanogenesis-related protein levels, such as microphthalmia? associated transcription factor (MITF), TRP-1, and TRP-2, without any cytotoxicity. Two active ingredients of D. morbiferus, (10E)-9,16-dihydroxyoctadeca-10,17-dien-12,14-diynoate (DMW-1) and (10E)-(?)-10,17-octadecadiene-12,14-diyne-1,9,16-triol (DMW-2) were identified by testing the anti-melanogenic effects and then by liquid chromatography-tandem mass spectrometry (LC/MS/MS) analysis. DMW-1 and DMW-2 significantly inhibited melanogenesis by the suppression of protein kinase A (PKA)/cyclic AMP (cAMP)-responsive binding protein (CREB) and p38 MAPK phosphorylation. DMW-1 showed a better inhibitory effect than DMW-2 in α-MSH-induced B16-F10 cells. D. morbiferus and its active component DMW-1 inhibited melanogenesis through the downregulation of cAMP, p-PKA/CREB, p-p38, MITF, TRP-1, TRP-2, and tyrosinase. These results indicate that D. morbiferus and DMW-1 may be useful ingredients for cosmetics and therapeutic agents for skin hyperpigmentation disorders.