Role of 5-HT2 and 5-HT7 Serotonin Receptors, and Protein Kinases C and A on Taurine Transport in Lymphocytes of Rats Treated with Fluoxetine

Author(s):  
María Colmenares-Aguilar ◽  
Lucimey Lima
2020 ◽  
Vol 7 (2) ◽  
pp. 205-211
Author(s):  
Kaynat Fatima ◽  
Syed Tasleem Raza ◽  
Ale Eba ◽  
Sanchita Srivastava ◽  
Farzana Mahdi

The function of protein kinases is to transfer a γ-phosphate group from ATP to serine, threonine, or tyrosine residues. Many of these kinases are linked to the initiation and development of human cancer. The recent development of small molecule kinase inhibitors for the treatment of different types of cancer in clinical therapy has proven successful. Significantly, after the G-protein-coupled receptors, protein kinases are the second most active category of drug targets. Imatinib mesylate was the first tyrosine kinase inhibitor (TKI), approved for chronic myeloid leukemia (CML) treatment. Imatinib induces appropriate responses in ~60% of patients; with ~20% discontinuing therapy due to sensitivity, and ~20% developing drug resistance. The introduction of newer TKIs such as, nilotinib, dasatinib, bosutinib, and ponatinib has provided patients with multiple options. Such agents are more active, have specific profiles of side effects and are more likely to reach the necessary milestones. First-line treatment decisions must be focused on CML risk, patient preferences and comorbidities. Given the excellent result, half of the patients eventually fail to seek first-line treatment (due to discomfort or resistance), with many of them needing a third or even further therapy lines. In the present review, we will address the role of tyrosine kinase inhibitors in therapy for chronic myeloid leukemia.


Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 875
Author(s):  
Gerald Thiel ◽  
Tobias Schmidt ◽  
Oliver G. Rössler

Ca2+ ions function as second messengers regulating many intracellular events, including neurotransmitter release, exocytosis, muscle contraction, metabolism and gene transcription. Cells of a multicellular organism express a variety of cell-surface receptors and channels that trigger an increase of the intracellular Ca2+ concentration upon stimulation. The elevated Ca2+ concentration is not uniformly distributed within the cytoplasm but is organized in subcellular microdomains with high and low concentrations of Ca2+ at different locations in the cell. Ca2+ ions are stored and released by intracellular organelles that change the concentration and distribution of Ca2+ ions. A major function of the rise in intracellular Ca2+ is the change of the genetic expression pattern of the cell via the activation of Ca2+-responsive transcription factors. It has been proposed that Ca2+-responsive transcription factors are differently affected by a rise in cytoplasmic versus nuclear Ca2+. Moreover, it has been suggested that the mode of entry determines whether an influx of Ca2+ leads to the stimulation of gene transcription. A rise in cytoplasmic Ca2+ induces an intracellular signaling cascade, involving the activation of the Ca2+/calmodulin-dependent protein phosphatase calcineurin and various protein kinases (protein kinase C, extracellular signal-regulated protein kinase, Ca2+/calmodulin-dependent protein kinases). In this review article, we discuss the concept of gene regulation via elevated Ca2+ concentration in the cytoplasm and the nucleus, the role of Ca2+ entry and the role of enzymes as signal transducers. We give particular emphasis to the regulation of gene transcription by calcineurin, linking protein dephosphorylation with Ca2+ signaling and gene expression.


2012 ◽  
Vol 23 (1) ◽  
pp. 22-35 ◽  
Author(s):  
Barbara Widmann ◽  
Franziska Wandrey ◽  
Lukas Badertscher ◽  
Emanuel Wyler ◽  
Jens Pfannstiel ◽  
...  

RIO proteins form a conserved family of atypical protein kinases. Humans possess three distinct RIO kinases—hRio1, hRio2, and hRio3, of which only hRio2 has been characterized with respect to its role in ribosomal biogenesis. Here we show that both hRio1 and hRio3, like hRio2, are associated with precursors of 40S ribosomal subunits in human cells. Furthermore, we demonstrate that depletion of hRio1 by RNA interference affects the last step of 18S rRNA maturation and causes defects in the recycling of several trans-acting factors (hEnp1, hRio2, hLtv1, hDim2/PNO1, and hNob1) from pre-40S subunits in the cytoplasm. Although the effects of hRio1 and hRio2 depletion are similar, we show that the two kinases are not fully interchangeable. Moreover, rescue experiments with a kinase-dead mutant of hRio1 revealed that the kinase activity of hRio1 is essential for the recycling of the endonuclease hNob1 and its binding partner hDim2 from cytoplasmic pre-40S. Kinase-dead hRio1 is trapped on pre-40S particles containing hDim2 and hNob1 but devoid of hEnp1, hLtv1, and hRio2. These data reveal a role of hRio1 in the final stages of cytoplasmic pre-40S maturation.


2016 ◽  
Vol 101 (8) ◽  
pp. 1064-1074 ◽  
Author(s):  
R. Forcén ◽  
E. Latorre ◽  
J. Pardo ◽  
A. I. Alcalde ◽  
M. D. Murillo ◽  
...  

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