Hippocalcin increases phospholipase D2 expression through extracellular signal-regulated kinase activation and lysophosphatidic acid potentiates the hippocalcin-induced phospholipase D2 expression

Oh, Doo-Yi,Yon, Changsuek,Oh, Kyoung-Jin,Lee, Ki Sung,Han, Joong-Soo Wiley Subscription Services, Inc., A Wiley Company 2006 Journal of cellular biochemistry Vol.97 No.5

<P>We have previously isolated a 22 kDa protein from a rat brain which was found to be involved in activating phospholipsae D (PLD), and identified the protein as hippocalcin through sequence analysis. Nevertheless, the function of hippocalcin for PLD activation still remains to be resolved. Here, we proposed that hippocalcin was involved in extracellular signal-regulated kinase (ERK)-mediated PLD2 expression. To elucidate a role of hippocalcin, we made hippocalcin transfected NIH3T3 cells and showed that the expression of PLD2 and basal PLD activity were increased in hippocalcin transfected cells. We performed PLD assay with dominant negative PLD2 (DN-PLD2) and hippocalcin co-transfected cells. DN-PLD2 suppressed increase of basal PLD activity in hippocalcin transfected cells, suggesting that increased basal PLD activity is due to PLD2 over-expression. Hippocalcin is a Ca<SUP>2+</SUP>-binding protein, which is expressed mainly in the hippocampus. Since it is known that lysophosphatidic acid (LPA) increases intracellular Ca<SUP>2+</SUP>, we investigated the possible role of hippocalcin in the LPA-induced elevation of intracellular Ca<SUP>2+</SUP>. When the intracellular Ca<SUP>2+</SUP> level was increased by LPA, hippocalcin was translocated to the membrane after LPA treatment in hippocalcin transfected cells. In addition, treatment with LPA in hippocalcin transfected cells markedly potentiated PLD2 expression and showed morphological changes of cell shape suggesting that increased PLD2 expression acts as one of the major factors to cause change of cell shape by making altered membrane lipid composition. Hippocalcin-induced PLD2 expression potentiated by LPA in hippocalcin transfected cells was inhibited by a PI-PLC inhibitor, U73122 and a chelator of intracellular Ca<SUP>2+</SUP>, BAPTA–AM suggesting that activation of hippocalcin caused by increased intracellular Ca<SUP>2+</SUP> is important to induce over-expression of PLD2. However, downregulation of PKC and treatment of a chelator of extracellular Ca<SUP>2+</SUP>, EGTA had little or no effect on the inhibition of hippocalcin-induced PLD2 expression potentiated by LPA in the hippocalcin transfected cells. Interestingly, when we over-express hippocalcin, ERK was activated, and treatment with LPA in hippocalcin transfected cells significantly potentiated ERK activation. Specific inhibition of ERK dramatically abolished hippocalcin-induced PLD2 expression. Taken together, these results suggest for the first time that hippocalcin can induce PLD2 expression and LPA potentiates hippocalcin-induced PLD2 expression, which is mediated by ERK activation. J. Cell. Biochem. 97: 1052–1065, 2006. © 2005 Wiley-Liss, Inc.</P>

Genistein과 Calphostin C를 이용한 T98G 세포와 Hs 683 세포에서의 PLC활성과 세포증식의 관계에 대한 연구

최창명,김윤,김보연,양지호,이일우,정철구,강준기 대한신경외과학회 1998 Journal of Korean neurosurgical society Vol.27 No.8

파노라마 촬영시 눈과 갑상선에 미치는 표면선량에 관한 연구

동경래(Dong Kyung-Rae) 한국콘텐츠학회 2009 한국콘텐츠학회 종합학술대회 논문집 Vol.7 No.1

파노라마 촬영 시 눈과 갑상선의 표면선량 실험은 광주지역 10개 병원을 대상으로 열형광선량계(Thermoluminescent dosimeter, TLD)와 형광유리선량계(Photoluminescent dosimeter, PLD)를 이용하여 각각 병원에서 사용하는 조건으로 측정(measurement)하였다. ICRP 60과 ICRP 73에서 권고한 눈에 대한 허용기준은 15mSv, 갑상선에 대한 허용기준은 연간 1mSv이다. 왼쪽 눈(Left Eye)의 TLD와 PLD값은 각각 0.19mSv와 0.24mSv, 오른쪽 눈(Right Eye)의 TLD와 PLD의 값은 0.23mSv와 0.25mSv, 갑상선의 TLD와 PLD의 값은 0.08mSv와 0.25mSv로 허용기준치를 초과하지 않았다. 또한 각 장기에 대한 TLD와 PLD의 비교에서는 왼쪽 눈과 갑상선이 유의한 차이가 있다고 볼 수 있고(p<0.01), 오른쪽 눈은 유의한 차이가 없다고 볼 수 있다(p>0.05). 각 병원에서 사용하는 파노라마 기기로 눈과 갑상선에 미치는 선량을 TLD와 PLD로 측정 하였을 때 눈과 갑상선의 표면선량은 ICRP 60에서 권고한 선량을 넘지 않았지만, 확률적 영향이 일어날 수 있으므로 모든 준위의 선량에 대해서 고려되어야 한다. Ten hospitals from the Gwangju area were used to examine shallow dose to eyes and thyroid from panoramagraphy. Thermoluminescent dosimeter (TLD) and Photoluminescent dosimeter (PLD) were used as measurement devices at each hospital. ICRP 60 and ICRP 73 set standards for acceptability for eyes at 15mSv and thyroid at 1mSv per year. Left eye measures with TLD and PLD resulted in 0.19mSv and 0.24mSv respectively. Right eye measures with TLD and PLD resulted in 0.23mSv and 0.25mSv respectively. Thyroid measures with TLD and PLD resulted in 0.08mSv and 0.25mSv respectively with both measures not exceeding standards for acceptance. There was a significant difference in comparing the left eye and thyroid for TLD and PLD (p<0.01). There was no significant difference with the right eye (p>0.05). The absorbed dose measurements for eyes and thyroid using TLD and PLD in regards to panorama devices at each hospital were within the ICRP 60 recommendations; however, with the possibility of stochastic effect, all dose levels were taken into consideration.

Activation of Phospholipase D2 through Phosphorylation of Tyrosine-470 in Antigen-stimulated Mast Cells

김영미,Kim Young Mi Korean Society of Life Science 2005 생명과학회지 Vol.15 No.3

The mechanism of activation of phospholipase D2 (PLD2) remains undefined although mechanisms have been described for the activation of PLDI. By expression of mutated forms of haemaglutinnin-tagged PLD2 in a mast cell (RBL-2H3) line, we show that PLD2 is phosphorylated at tyrosines -11, -14, and -470 and that tyrosine-470 is critical for activation of PLD2 by antigen. Studies were performed with mutated-DNA constructs for haemaglutinnin-tagged PLD2 in which codons for tyrosine -11, -14, -165, and -470 were mutated to phenylalanine either individually or collectively. Transient expression of these constructs showed that mutation of tyrosine -11, -14, -470, or all tyrosines (all-mutated PLD2) suppressed antigen-induced tyrosine phosphorylation of PLD2 but only the tyrosine-470 mutant failed to be activated by antigen as assessed by in vitro assay of immunoprepitated PLD2 or by assay of PLD in intact cells. The critical role of tyrosine-470 was confirmed in studies with add-back mutants (phenylalanine back to tyrosine) of the all-mutated PLD. The findings provide the first description of a mechanism of activation of PLD2 in a physiological setting.

Phospholipase D in Guinea Pig Lung Tissue Membrane is Regulated by Cytosolic ARF Proteins

( Yean Jun Chung ),( Jin Rak Jeong ),( Byung Chul Lee ),( Ji Young Kim ),( Young In Park ),( Jai Youl Ro ) 한국미생물생명공학회 2003 Journal of Microbiology and Biotechnology Vol.13 No.6

Over-Expression of Phospholipase D Isozymes Down-Regulates Protein Kinase CKII Activity via Proteasome-Dependent CKII Degradation in NIH3T3 Cells

윤수현,민도식,Young-Seuk Bae 한국분자세포생물학회 2009 Molecules and cells Vol.27 No.3

Over-expression of phospholipase D (PLD) 1 or PLD2 downregulated CKII activity in NIH3T3 cells. The same results were found with catalytically inactive mutants of PLD isozymes, indicating that the catalytic activity of PLD is not required for PLD-mediated CKII inhibition. Consistent with this, 1-butanol did not alter CKII activity. The reduction in CKII activity in PLD-over-expressing NIH3T3 cells was due to reduced protein level, but not mRNA level, of the CKIIβ subunit. This PLD-induced CKIIβ degradation was mediated by ubiquitin-proteasome machinery, but MAP kinase and mTOR were not involved in CKIIβ degradation. PLD isozymes interacted with the CKIIβ subunit. Immunocytochemical staining revealed that PLD and CKIIβ colocalize in the cytoplasm of NIH3T3 cells, especially in the perinuclear region. PLD binding to CKIIβ inhibited CKIIβ autophosphorylation, which is known to be important for CKIIβ stability. In summary, the current data indicate that PLD isozymes can down-regulate CKII activity through the acceleration of CKIIβ degradation by ubiquitin-proteasome machinery.

공유결합으로 다공성 막에 고정화된 PLD에 의한 포스퍼티딕산 생산

박진원(Jin-Won Park) 한국청정기술학회 2015 청정기술 Vol.21 No.4

Comparative Analysis of Phospholipase D2 Localization in the Pancreatic Islet of Rat and Guinea Pig

Ryu, Gyeong-Ryul,Kim, Myung-Jun,Song, Chan-Hee,Min, Do-Sik,Rhie, Duck-Joo,Yoon, Shin-Hee,Hahn, Sang-June,Kim, Myung-Suk,Jo, Yang-Hyeok The Korean Society of Pharmacology 2003 The Korean Journal of Physiology & Pharmacology Vol.7 No.4

To examine the localization pattern of phospholipase D2 (PLD2) in the pancreatic islet (the islet of Langerhans) depending on species, we conducted a morphological experiment in the rat and guinea pig. Since individual islets display a typical topography with a central core of B cell mass and a peripheral boundary of A, D, and PP cells, double immunofluorescent staining with a panel of antibodies was performed to identify PLD2-immunoreactive cells in the islets PLD2 immunoreactivity was mainly present in A and PP cells of the rat pancreatic islets. And yet, in the guinea pig, PLD2 immunoreactivity was exclusively localized in A cells, and not in PP cells. These findings suggest a possibility that PLD2 is mainly located in A cells of rodent pancreatic islets, and that the existence of PLD2 in PP cells is not universal in all species. Based on these results, it is suggested that PLD2 may play a significant role in the function of A and/or PP cells via a PLD-mediated signaling pathway.

Phospholipase D1 Signaling: Essential Roles in Neural Stem Cell Differentiation

Park, Shin-Young,Han, Joong-Soo Springer US 2018 Journal of molecular neuroscience Vol.64 No.3

<P>Phospholipase D1 (PLD1) is generally accepted as playing an important role in the regulation of multiple cell functions, such as cell growth, survival, differentiation, membrane trafficking, and cytoskeletal organization. Recent findings suggest that PLD1 also plays an important role in the regulation of neuronal differentiation of neuronal cells. Moreover, PLD1-mediated signaling molecules dynamically regulate the neuronal differentiation of neural stem cells (NSCs). Rho family GTPases and Ca<SUP>2+</SUP>-dependent signaling, in particular, are closely involved in PLD1-mediated neuronal differentiation of NSCs. Moreover, PLD1 has a significant effect on the neurogenesis of NSCs via the regulation of SHP-1/STAT3 activation. Therefore, PLD1 has now attracted significant attention as an essential neuronal signaling molecule in the nervous system. In the current review, we summarize recent findings on the regulation of PLD1 in neuronal differentiation and discuss the potential role of PLD1 in the neurogenesis of NSCs.</P>

형광유리 선량계와 광자극 발광선량계를 이용한 핵의학과 선량 측정비교

박정규,손상준,박명환 대한방사선과학회 2019 방사선기술과학 Vol.42 No.1

This study was conducted from July 1 to September 30, 2018 using Optically Stimulated Luminescence Dosimeter(OSLD) and photoluminescent glass dosimeter(PLD) to measure the 3-month exposure dose and the cumulative dose in the active working area of the nuclear medicine worker Respectively. As a result, the cumulative dose for three months in the worker and work area was measured as 1.97 mSv and 2.02 mSv in the PLD. The mean surface dose and the mean depth dose of the OSLD were measured to be 2.04 mSv. The difference in the total surface dose measured by the PLD and the OSLD was 0.66mSv and the total mean surface dose was 0.07mSv. The difference between the total depth dose and the total depth dose was 0.1mSv and 0.02mSv, respectively. It was found that the dose value of the OSLD was higher than that of the PLD. In addition, it was found that the maximum difference of 0.01mSv was observed between the PLD and the OSLD of the worker. For the dose measurement of the two dosimetry systems, there was no significant difference between the PLD and the OSLD in the surface dose of 0.239 (p>0.05). Also, the significance of PLD and OSLD in the deep dose was 0.109, which was not statistically significant (p>0.05).