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1

Regulation of calcium channel in the plasma membrane of hepatoma H-35

100%

Niewczas B., Duszynski J.

Biophysics of Membrane Transport

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1994

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tom 12

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nr 2

2

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RER and protamine-type proteins during Chara tomentosa L. spermiogenesis

88%

Kwiatkowska M., Poplonska K.

Acta Societatis Botanicorum Poloniae

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2003

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tom 72

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nr 1

In Chara tomentosa during mid spermiogenesis (phases V, VI, VII) when the amount of nuclear protamine-type proteins increases, while the amount of histones decreases, in connection with chromatin remodelling, an extensive RER system filled with dark, fine-granular substance is observed. The intermembranous space of the nuclear envelope is filled with a homogenous substance which looks similar. The most extensive ER system can be observed in phase V, which is at the beginning of nuclear protein exchange. The results presented in this paper correspond with the earlier suggestion based on Chara vulgaris spermioge nesis studies, that ER takes part in a protamine-type protein synthesis, which enter a nucleus by endocytosis, through an inner nuclear envelope membrane.

3

Endoplasmic reticulum quality control and apoptosis

88%

Groenendyk J., Michalak M.

Acta Biochimica Polonica

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2005

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tom 52

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nr 2

The ER is one of the most important folding compartments within the cell, as well as an intracellular Ca2+ storage organelle and it contains a number of Ca2+ regulated molecular chaperones responsible for the proper folding of glycosylated as well as non-glycosylated proteins. The luminal environment of the ER contains Ca2+ which is involved in regulating chaperones such as calnexin and calreticulin, as well as apoptotic proteins caspase-12 and Bap31, which may play an important role in determining cellular sensitivity to ER stress and apoptosis. The ER quality control system consists of several molecular chaperones, including calnexin, that assist in properly folding proteins and transporting them through the ER as well as sensing misfolded proteins, attempting to refold them and if this is not possible, targeting them for degradation. Accumulation of misfolded protein in the ER leads to activation of genes responsible for the expression of ER chaperones. The UPR mechanism involves transcriptional activation of chaperones by the membrane-localized transcription factor ATF6, in conjunction with the ER membrane kinase IRE1, as well as translational repression of protein synthesis by another ER membrane kinase PERK. When accumulation of misfolded protein becomes toxic, apoptosis is triggered, potentially with IRE1 involved in signaling via caspase-12. Both the extrinsic and intrinsic apoptotic pathways appear to culminate in the activation of caspases and this results in the recruitment of mitochondria in an essential amplifying manner. Bap31 may direct pro-apoptotic crosstalk between the ER and the mitochondria via Ca2+ in conjunction with caspase-12 and calnexin. Accordingly, ER stress and the resultant Ca2+ release must be very carefully regulated because of their effects in virtually all areas of cell function.

4

The role of Ca2-nH exchanger in the regulation of Ca2 concentration in lymphocytes

88%

Kucherenko S. N.

Biophysics of Membrane Transport

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1994

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tom 12

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nr 2

5

Subcellular localization of UDP-GlcNAc, UDP-Gal and SLC35B4 transporters

75%

Maszczak-Seneczko D., Olczak T., Olczak M.

Acta Biochimica Polonica

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2011

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tom 58

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nr 3

The mechanisms of transport and distribution of nucleotide sugars in the cell remain unclear. In an attempt to further characterize nucleotide sugar transporters (NSTs), we determined the subcellular localization of overexpressed epitope-tagged canine UDP-GlcNAc transporter, human UDP-Gal transporter splice variants (UGT1 and UGT2), and human SLC35B4 transporter splice variants (longer and shorter version) by indirect immunofluorescence using an experimental model of MDCK wild-type and MDCK-RCAr mutant cells. Our studies confirmed that the UDP-GlcNAc transporter was localized to the Golgi apparatus only and its localization was independent of the presence of endogenous UDP-Gal transporter. After overexpression of UGT1, the protein colocalized with the Golgi marker only. When UGT2 was overexpressed, the protein colocalized with the endoplasmic reticulum (ER) marker only. When UGT1 and UGT2 were overexpressed in parallel, UGT1 colocalized with the ER and Golgi markers and UGT2 with the ER marker only. This suggests that localization of the UDP-Gal transporter may depend on the presence of the partner splice variant. Our data suggest that proteins involved in nucleotide sugar transport may form heterodimeric complexes in the membrane, exhibiting different localization which depends on interacting protein partners. In contrast to previously published data, both splice variants of the SLC35B4 transporter were localized to the ER, independently of the presence of endogenous UDP-Gal transporter.

6

The effects of induced ER stress on ROS regulation and antioxidant defense in Arabidopsis thaliana under osmotic stress

75%

Ozgur R., Turkan I., Uzilday B., Sekmen A.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2013

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tom 94

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nr 2

7

Steroid hormone (prednisolone) influence on the unicellular Tetrahymena (an electron microscopic study)

75%

Csaba G., Fulop A. K.

Acta Protozoologica

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1987

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tom 26

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nr 3

8

Role of sulfation in the processing of gastric mucins

75%

Liau Y. H., Murty V. L. N., Slomiany A., Bielanski W., Slomiany B. L.

Journal of Physiology and Pharmacology

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1991

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tom 42

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nr 4

The role of sulfation in the processing of mucus glycoprotein in gastric mucosa was investigated. Rat gastric mucosal segments were incubated in MEM at various medium sulfate concentrations in the presence of [³⁵S]Na₂ SO₄ [³H] glucosamine and [³H]proline, with and without chlorate an inhibitor of PAPS formation. The results revealed that the mucin sulfation attained maximum at 300 µM medium sulfate concentration. Introduction of chlorate into the incubation medium, while having no effect on the protein synthesis as evidenced by [³H]proline incorporation, caused at its optimal concentration of 2 mM a 90% decrease in mucin sulfation and a 40% drop in mucin glycosylation. Evaluation of mucin molecular forms distribution indicated the predominance of the high molecular mucin form in the interacellular fraction and the low molecular mucin from in the extracellular fraction. Increase in medium sulfate caused an increase in the high molecular weight mucin form in both fractions, and this effect was inhibited by chlorate. Also, higher medium sulfate concentrations led to a higher degree of sulfation in the high molecular weight mucin form, the effect of which was inhibited by chlorate. The results suggest that the sulfation process is an early event taking place at the stage of mucin subunit assembly and is required for mucin polymer formation. Hence, the disturbances in mucin sulfation process could be determinal to the maintenance of gastric mucus coat integrity.

9

Mitochondrial uncoupling does not influence the stability of the intracellular signal activating plasma membrane calcium channels

75%

Zablocki K., Makowska A., Duszynski J.

Acta Biochimica Polonica

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2001

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tom 48

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nr 1

The effects of various concentrations of thapsigargin, a specific inhibitor of Ca2+ -ATPase in the endoplasmic reticulum (ER) membrane, on calcium homeostasis in lymphoidal T cells (Jurkat) were investigated. Preincubation of these cells suspended in nominally calcium-free medium with 0.1 UM thapsigargin resulted in a complete release of Ca2+ from intracellular calcium stores. When the medium was supplemented with 3 mM CaCl2 the cells maintained constantly elevated level of cytosolic Ca2+ . However, thapsigargin applied at lower concentration produced only a partial depletion of the stores. For example, in the cells pretreated with 1 nM thapsigargin and suspended in calcium-free medium approximately 75% of the calcium content was released from the intracellular stores. The addition of 3 mM CaCl2 to such cell suspension led to a transient increase in cytosolic calcium concentration, followed by a return to a lower steady-state. This phenomenon, related to the refilling of the ER by Ca2+ , allowed to estimate the half-time for the process of cell recovery after activation of store-operated calcium channels. By this approach we have found that carbonyl cyanide m-chlorophenylhydrazone, which has been documented to inhibit calcium entry into Jurkat cells, does not influence the stability of the intracellular signal involved in the activation of store-operated calcium channels.

10

Development of the tapetum cells in the natural tetraploid red clover [Trifolium pratense L.]

75%

Buyukkartal H. N. B., Algan G.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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1999

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tom 41

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nr 1

11

Thapsigargin: potent inhibitor of Ca2 transport ATP-ases of endoplasmic and sarcoplasmic reticulum

75%

Sabala P., Czarny M., Woronczak J. P., Baranska J.

Acta Biochimica Polonica

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1993

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tom 40

|

nr 3

12

Calreticulin biochemical characterization during induction of somatic embryogenesis in the wild type and mutant [ts11] cell suspension culture of Daucus carota L.

75%

Libik M.

Acta Biologica Cracoviensia. Series Botanica et Zoologia. Supplement

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1997

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tom 39

|

nr 1

13

Gastric mucosal cell hemeostatic physiome. Critical role of ER-initiated membranes restitution in the fidelity of cell function renewal

75%

Slomiany A., Sano S., Grabska M., Yamaki K., Slomiany B. L.

Journal of Physiology and Pharmacology

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2004

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tom 55

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nr 4

Homeostatic cell physiology is preserved through the fidelity of the cell membranes restitution. The task is accomplished through the assembly of the precisely duplicated segments of the cell membranes, and transport to the site of their function. Here we examined the mechanism that initiates and directs the restitution of the intra- and extracellular membranes of gastric mucosal cell. The homeostatic restitution of gastrointestinal epithelial cell membrane components was investigated by studying the lipidomic processes in endoplasmic reticulum (ER) and Golgi. The biomembrane lipid synthesis during the formation of transport vesicles in the systems containing isolated organelle and the cell-specific cytosol (Cyt) from rat gastric mucosal epithelial cells was assessed. The results revealed that lipids of ER transport vesicle and the transmembrane and intravesicular cargo are delivered en bloc to the point of destination. En bloc delivery of proteins, incorporated into predetermined in ER lipid environment, ensures fidelity of the membrane modification in Golgi and the restitution of the lipid and protein elements that are consistent with the organelle and the cell function. The mechanism that maintains apical membrane restitution is mediated through the synthesis of membrane segments containing ceramide (Cer). The Cer-containing membranes and protein cargo are further specialized in Golgi. The portion of the vesicles destined for apical membrane renewal contains glycosphingolipids and phosphatidylinositol 3-phosphate. The vesicles containing phosphatidylinositol 4-phosphate are directed to endosomes. Our findings revealed that the preservation of the physiological equilibrium in cell structure and function is attributed to (1) a complete membrane segment synthesis in ER, (2) its transport in the form of ER-transport vesicle to Golgi, (3) the membrane components-defined maturation of lipids and proteins in Golgi, and (4) en bloc transfer of the new segment of the membrane to the cell apical membrane or intracellular organelle.

14

Energy - dependent transport of Ca2 in the intracellular structures of the smooth muscle

75%

Babich L. G., Shlykov S. G., Borysova L. A., Kosterin S. A.

Biophysics of Membrane Transport

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1994

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tom 12

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nr 2

15

A recent approach to the study of dolichol monophosphate topology in the rough endoplasmic reticulum

75%

Banerjee D. K.

Acta Biochimica Polonica

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1994

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tom 41

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nr 3

Amphomycin though withdrawn as an antibiotic against the gram-positive bacterial infection, can certainly serve as an excellent tool for determination of the topology of Dol-P in the endoplasmic reticulum membranes, which has been otherwise impossible.

16

Further ultrastructural research of Chara vulgaris spermiogenesis: endoplasmic reticulum, structure of chromatin, 3H-lysine and 3H-arginine incorporation

75%

Kwiatkowska M., Poplonska K.

Folia Histochemica et Cytobiologica

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2002

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tom 40

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nr 2

17

Effect of pulsed electromagnetic fields on endoplasmic reticulum stress

63%

Keczan E., Keri G., Banhegyi G., Stiller I.

Journal of Physiology and Pharmacology

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2016

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tom 67

|

nr 5

18

Biochemical and stereological investigations of rough endoplasmic reticulum (RER) of regenerating rat liver

63%

Jaszczuk-Jarosz B., Turski W. A., Bartel H.

Folia Histochemica et Cytobiologica

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1984

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tom 22

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nr 2

19

Perillyl alcohol, a pleiotropic natural compound suitable for brain tumor therapy, targets free radicals

63%

Gomes A. C., Mello A. L., Ribeiro M. G., Garcia D. G., Da Fonseca C. O., D’Alincourt Salazar M., Schonthal A. H., Quirico-Santos T.

Archivum Immunologiae et Therapiae Experimentalis

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2017

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tom 65

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nr 4

20

Training induced decrease in oxygen cost of cycling is accompanied by down-regulation of SERCA expression in human vastus lateralis muscle

63%

Majerczak J., Karasinski J., Zoladz J. A.

Journal of Physiology and Pharmacology

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2008

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tom 59

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nr 3

589-602

We have examined the effect of 5 week cycling endurance training program on the sarco(endo)plasmic reticulum Ca2+ ATPase isoforms (SERCA1 and 2) and myosin heavy chain (MyHC) in the vastus lateralis muscle as well as on the oxygen uptake to power output ratio (VO2/PO) during incremental cycling. Fifteen untrained men performed an incremental cycling exercise until exhaustion before and after moderate intensity training. Muscle biopsies were taken from vastus lateralis before and after training program. Training resulted in higher (P = 0.048) maximal oxygen uptake (VO2max) as well as in higher power output reached at VO2max (P = 0.0001). Moreover, lower (P = 0.02) VO2/PO ratio determined during incremental moderate intensity cycling (i.e. 30-120 W) as well as lower (P = 0.003) VO2/PO ratio reached at VO2max were observed after the training. A significant down regulation of SERCA2 protein (P = 0.03) and tendency (P = 0.055) to lower SERCA1 content accompanied by lower (P<10-4) plasma thyroid hormone concentration, with no changes (P = 0.67) in MyHC composition in vastus lateralis muscle were found after training. We have concluded that the increase in mechanical efficiency of cycling occurring during first weeks of endurance training is not related to changes in MyHC composition but it may be due to down-regulation of SERCA pumps.

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