• BMB Reports
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• 제43권3호
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• pp.158-163
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• 2010

Calumenin is a multiple EF-hand $Ca^{2+}$-binding protein located in the endo/sarcoplasmic reticulum of mammalian hearts. Calumenin belongs to the CREC family of $Ca^{2+}$-binding proteins having multiple EF-hands. $Ca^{2+}$ homeostasis in the sarcoplasmic reticulum (SR) of mammalian hearts is maintained by RyR2, SERCA2 and other associated SR resident proteins. Evidence suggests that calumenin interacts with RyR2 and SERCA2, and therefore changes in the expression of calumenin could alter $Ca^{2+}$ cycling in mouse heart. In this review, current knowledge of the biochemical and functional roles of calumenin in mouse heart is described.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1999년도 학술발표회 진행표 및 논문초록
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• pp.57-57
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• 1999

It is well known that rapidly activating delayed rectifier $K^{＋}$ channels ( $I_{Kr}$ ) playa role in repolarisation in mammalian hearts. Recently, human ether-a- go- go related gene (HERG) channels was shown to be a molecular equivalent to $I_{Kr}$ . We have investigated the permeation of various external cations on $I_{Kr}$ in mammalian hearts and on HERG channels expressed in Xenopus laevis oocytes.(omitted)

• Current Optics and Photonics
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• 제3권1호
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• pp.1-7
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• 2019

Optical stimulation provides a promising alternative to electrical stimulation to selectively modulate tissue. However, developing noninvasive techniques to directly stimulate excitable tissue without introducing genetic modifications and minimizing cellular stress remains an ongoing challenge. Infrared (IR) light has been used to achieve optical pacing for electrophysiological studies in embryonic quail and mammalian hearts. Here, we demonstrate optical stimulation and pacing of the embryonic chicken heart using a pulsed infrared thulium laser with a wavelength of 1927 nm. By recording stereomicroscope outputs and quantifying heart rates and movements through video processing, we found that heart rate increases instantly following irradiation with a large spot size and high radiant exposure. Targeting the atrium using a smaller spot size and lower radiant exposure achieved pacing, as the heart rate synchronized with the laser to 2 Hz. This study demonstrates the viability of using the 1927 nm thulium laser for cardiac stimulation and optical pacing, expanding the optical parameters and IR lasers that can be used to modulate cardiac dynamics.

• 한국패류학회지
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• 제25권1호
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• pp.15-22
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• 2009

Because it is known that bivalve hearts contain various modulatory systems activated by neuroendocrine substances, it was examined whether different classes of endogenous and synthetic drugs of neuroendocrinological importance can influence cardiac functions of the Pacific oyster Crassostrea gigas. Cholinergically active agents acetylcholine and carbachol increased heart rates while diminishing cardiac contractility. Adrenergically active substances norepinephrine (NE) and epinephrine (Epi) also induced heart rate increase and contractility decrease. An $\alpha_1$-adrenergic receptor-selective agonist phenyephrine (PE) failed to modulate either parameter. The Epi-induced heart rate increase and contractile depression were both blocked significantly by non-selective $\beta_1/\beta_2$-adrenergic antagonist propranolol. A $\beta_1$-selective antagonist atenolol prevented Epi-induced heart rate decrease but not the contractile depression, suggesting possible $\beta_2$ receptors for Epi-induced contractile depression. The three autacoids examined exerted discrete responses: histamine increased heart rate and depressed contraction; $\gamma$-amino-butyric acid increased both parameters; serotonin failed to change either parameter. The 5 piscine anesthetic agents examined, MS-222, benzocaine, quinaldine, urethane, pantocaine and pentobarbital, all failed to influence the cardiac function of oysters. Collectively, activities of neuroendocrinologically acting agents in mammals showed unexpected and distinct activities from those in mammalian cardiovascular systems. These results obtained from substances of different physiological functions can serve as a basis for understanding neuroendocrine control of the heart function in Pacific oyster.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.234-241
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• 2001

The C-terminal 393 bp region of the human interleukin-16 (IL-16) gene was cloned and expressed in E. coli along with mammalian cell lines. Recombinant IL-16 expressed from E. coli was 22 kDa on SDS-PAGE and showed 260% of chemoattractant activity at a concentration of $0.1\;{\mu}g/ml$. HeLa, COS, and Neuro-2a cells were transduced by recombinant retrovirus vector pLNC/IL-16/IRES/TK and the intracellular and secreted amounts of IL-16 produced by HeLa/IL-16/TK, COS/IL-16/TK, and Neuro-2a/IL-16/TK cells were determined by enzyme-linked immunosorbent assay (ELISA). HeLa/IL-16/TK $(1{\times}10^5)$ and COS/IL-16/TK $(1{\times}10^5)$ cells secreted 36.1 and 13.3 ng of IL-16 for 48 h, respectively. Forty-nine ng and 86.4 ng of IL-16 remained in the cell lysates of HeLa/IL-16/TK and COS/IL-16/TK. Intracellular and secreted amounts of IL-16 from Neuro-2a/IL-16/TK $(5{\times}10^5)$ cells during 24 h cultivation were 50 ng and 3.3 ng, respectively. Also, HeLa and COS cells wee stably transfected with mammalian expression vector pCRIII/IL-16. Both culture media and cell lysates prepared from HeLa/IL-16 cells and COS/IL-16 cells showed chemoattractant activity ranging from 190% to 460% as compared to the control experiment. Expression of the herpes simplex virus thymidine kinase (HSV0tk) gene in pLNC/IL-16/ IRES/TK bicistronic retroviral expression vector was verified by performing a genciclovir (GCV) sensitivity assay. Finally, IL-16 repressed Tat-transactivated human immunodeficiency virus type 1 long terminal repeat (HIV-1 LTR) promoter activity.

• Molecules and Cells
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• 제26권3호
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• pp.265-269
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• 2008

Calumenin, a multiple EF-hand $Ca^{2+}$ binding protein is located in the SR of mammalian heart, but the functional role of the protein in the heart is unknown. In the present study, an adenovirus gene transfer system was employed for neonatal rat heart to examine the effects of calumenin over-expression (Calu-OE) on $Ca^{2+}$ transients. Calu-OE (8 folds) did not alter the expression levels of DHPR, RyR2, NCX, SERCA2, CSQ and PLN. However, Calu-OE affected several parameters of $Ca^{2+}$ transients. Among them, prolongation of time to 50% baseline ($T_{50}$) was the most outstanding change in electrically-evoked $Ca^{2+}$ transients. The higher $T_{50}$ was due to an inhibition of SERCA2-mediated $Ca^{2+}$ uptake into SR, as tested by oxalate-supported $Ca^{2+}$ uptake. Furthermore, co-IP study showed a direct interaction between calumenin and SERCA2. Taken together, calumenin in the cardiac SR may play an important role in the regulation of $Ca^{2+}$ uptake during the EC coupling process.

• BMB Reports
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• 제43권5호
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• pp.355-362
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• 2010

The sterile alpha motif (SAM) is a putative protein interaction domain involved in a wide variety of biological processes. Here we report the identification and characterization of a novel gene, SAMD4B, which encodes a putative protein of 694 amino acids with a SAM domain. Northern blot and RT-PCR analysis showed that SAMD4B is widely expressed in human embryonic and adult tissues. Transcriptional activity assays show SAMD4B suppresses transcriptional activity of L8G5-luciferase. Over-expression of SAMD4B in mammalian cells inhibited the transcriptional activities of activator protein-1 (AP-1), p53 and p21, and the inhibitory effects can be relieved by siRNA. Deletion analysis indicates that the SAM domain is the main region for transcriptional suppression. The results suggest that SAMD4B is a widely expressed gene involved in AP-1-, p53- and p21-mediated transcriptional signaling activity.

• BMB Reports
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• 제43권6호
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• pp.432-437
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• 2010

LBH is a transcription factor as a candidate gene for CHD associated with partial trisomy 2p syndrome. To identify potential LBH-interacting partners, a yeast two-hybrid screen using LBH as a bait was performed with a human heart cDNA library. One of the clones identified encodes ${\alpha}B$-crystallin. Co-immunoprecipitation and GST pull-down assays showed that LBH interacts with ${\alpha}B$-crystallin, which is further confirmed by mammalian two-hybrid assays. Co-localization analysis showed that in COS-7 cells, ${\alpha}B$-crystallin that is cytoplasmic alone, accumulates partialy in the nucleus when co-transfected with LBH. Transient transfection assays indicated that overexpression of LBH or ${\alpha}B$-crystallin reduced the transcriptional activities of p53 and p21, respectively, Overexpression of both ${\alpha}B$-crystallin and LBH together resulted in a stronger repression of the transcriptional activities of p21 and p53. These results showed that the interaction of LBH and ${\alpha}B$-crystallin may inhibit synergistically the transcriptional regulation of p53 and p21.

• 대한수의학회지
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• 제39권1호
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• pp.62-69
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• 1999

Although it has been reported that hormones or chemicals, which increase in intracellular cAMP, produced $Mg^{2+}$ release from the heart, it is not well characterized whether a specific $Mg^{2+}$ exchanger is involved in cAMP-induced $Mg^{2+}$ efflux in the mammalian hearts. In this work, we studied the relationship between the increase in intracellular cAMP and ion transport system on $Mg^{2+}$ regulation in the perfused rat heart and isolated myocytes. The $Mg^{2+}$ content in the perfusate and supernatant were measured by atomic absorption spectrophotometer. The addition of membrane permeable cAMP analogue to the perfused hearts and myocytes induced a $Mg^{2+}$ efflux in the dose dependent manners. $Mg^{2+}$ efflux was stimulated by cAMP modulators (forskolin, IBMX and Ro20-1724) in the perfused hearts and myocytes. cAMP-induced $Mg^{2+}$ efflux was inhibited by $H_7$, benzamil or imipramine in the perfused hearts and myocytes, but not by EIPA. We confirmed that a significant $Mg^{2+}$ efflux was induced by an increase in intracellular cAMP in the hearts and myocytes. The cAMP-induced increase of $Mg^{2+}$ efflux in the hearts may be involved in ion transport system ($Na^+-Ca^{2+}$ and $Na^+-Mg^{2+}$ exchanger).

• 한국양식학회지
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• 제17권1호
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• pp.1-7
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• 2004

A rainbow trout uncoupling protein 3 (UCP3) cDNA clone, encoding a 310 amino acid protein, was cloned and sequenced from a liver cDNA library. Two different splice variants designated UCP3-vl and UCP3-v2, were identified through liver cDNA library screening using rainbow trout UCP3 cDNA clone as a probe. UCP3-vl has 3 insertions in the UCP3 cDNA: the first insertion (133 bp), the second (141 bp), and the third (370 bp) were located 126 bp, 334 bp and 532 bp downstream from the start codon, respectively. UCP3-v2 contained a single insertion, identical in sequence and location to the second insertion of UCP3-vl. UCP3, a mitochondrial protein, functions to modulate the efficiency of oxidative phosphorylation. UCP3 has been detected from heart, testis, spinal cord, eye, retina, colon, muscle, brown adipose tissue and white adipose tissue in mammalian animals. Human and rodent UCP3s are highly expressed in skeletal muscle and brown adipose tissue, while they show weak expression of UCP3 in heart and white adipose tissue. In contrast to mammalian studies, RT-PCR and Southern blot analysis of the rainbow trout demonstrated that UCP3 is strongly expressed in liver and heart. UCP3, UCP3-vl, and UCP3-v2 all contain an Ava III short interspersed element (SINE), located in the 3'untraslated region (UTR). PCR using primers from the Ava III SINE and the UCP3 3'UTR region indicates that the UCP3 cDNA is structurally conserved among salmonids and that these primers may be useful for salmonid species genotyping.