Physiological stresses (heat, hemodynamics, genetic mutations, oxidative injury and myocardial ischemia) produce pathological states in which protein damage and misfolded protein structures are a common denominator. The specialized proteins family of antistress proteins - molecular chaperons (HSPs) - are responsible for correct protein folding, dissociating protein aggregates and transport of newly synthesized polypeptides to the target organelles for final packaging, degradation or repair. They are inducible at different cell processes such as cell division, apoptosis, signal transduction, cell differentiation and hormonal stimulation. HSPs are involved in numerous diseases including cardiovascular pathologies, revealing changes of expression and cell localization. We studied the possible changes in expression level of abundant mitochondrial chaperon Hsp60 and main human cytochrome P450 monooxygenase (2E1 isoform) at dilated cardiomyopathy (DCM) progression at the end stage of heart failure using Western blot analysis. The ischemic and normal humans' hearts were studied as control samples. We observed the decrease of Hsp60 level in cytoplasmic fraction of DCM- and ischemia-affected hearts' left ventricular and significant increase of Hsp60 in mitochondrial fractions of all hearts investigated. At the same time we detected the increase of P450 2E1 expression level in ischemic and dilated hearts' cytoplasmic fractions in comparison with normal myocardium and no detectable changes in microsomal fractions of hearts investigated which could be linked with increased level of oxidative injury for DCM heart muscle. In addition, all the changes described are accompanied by significant decrease of ATPase activity of myosin purified from DCM-affected heart in comparison with normal and ischemic myocardia as well. The data obtained allow us to propose a working hypothesis of functional link between antistress (HSPs) and antioxidative (cytochromes) systems at DCM progression.

To identify novel protein partners of translation factor eEF1Bβ in nucleus of human lung carcinoma cells. Methods. Protein partners of eEF1Bβ in the nuclear fraction of A549 cells were identified by co-immunoprecipitation (co-IP) combined with liquid chromatographytandem mass spectrometry (LC-MS/MS). Specific protein partners of eEF1Bβ were further selected by using the results of previously published global, quantitative and dynamic mapping of protein subcellular localization with help of "Mapofthecell" program. Results. 104 highscored proteins interacting with eEF1Bβ in the nuclear fraction of A549 cells have been identified by mass-spectrometry. Among these proteins, 9 partners of eEF1Bβ were confirmed by the co-fractionation approach. Functional analysis of the partners has divided them on the pro-oncogenic (lung-cancer related) and neutral/anti-oncogenic moieties. These two groups are estimated to be spatially separated in human cancer cells. Conclusions. The position of eEF1Bβ as a link between the oncogenic and neutral/tumor-suppressor moieties of its protein partners in nucleus of lung cancer cells is suggested. Deciphering of a possible role of the eEF1Bβ distribution between the pro-cancer or anti-cancer communities of its protein partners can be a subject of further research.

To predict protein networks which may comprise the β subunit of the translation elongation complex eEF1B in lung carcinoma cell line. Methods. The protein partners of eEF1Bβ from cytoplasmic extract of A549 cells were identified by co-immunoprecipitation (co-IP) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). The molecular interaction network for eEF1Bβ was predicted and visualized by a Cytoscape 3.2.0 program using an MCODE plugin. GO analysis of cellular distribution was performed by a STRAP program. Results. 162 high-scored proteins interacting with eEF1Bβ in the cytoplasm of lung carcinoma cells A549 have been identified by mass-spectrometry. Possible functional networks involving these contacts were predicted bioinformatically. Conclusions. Four protein networks are identified as possible targets of eEF1Bβ in lung cancer cells. These groups are involved in the cell cycle regulation; DNA replication and repair; chromatin remodeling; chaperoning and signal transduction. The data allow to narrow down further search for non-canonical cancer-related function of eEF1Bβ.

BackgroundThe constituents of stable multiprotein complexes are known to dissociate from the complex to play independent regulatory roles. The components of translation elongation complex eEF1H (eEF1A, eEF1Bα, eEF1Bβ, eEF1Bγ) were found overexpressed in different cancers. To gain the knowledge about novel cancer-related translational mechanisms we intended to reveal whether eEF1H exists as a single unit or independent subunits in different human cancers.MethodsThe changes in the expression level of every subunit of eEF1H in the human non-small-cell lung cancer tissues were examined. The localization of eEF1H subunits was assessed by immunohistochemistry methods, subcellular fractionation and confocal microscopy. The possibility of the interaction between the subunits was estimated by co-immunoprecipitation.ResultsThe level of eEF1Bβ expression was increased more than two-fold in 36%, eEF1Bγ in 28%, eEF1A in 20% and eEF1Bα in 8% of tumor specimens. The cancer-induced alterations in the subunits level were found to be uncoordinated, therefore the increase in the level of at least one subunit of eEF1H was observed in 52% of samples. Nuclear localization of eEF1Bβ in the cancer rather than distal normal looking tissues was found. In cancer tissue, eEF1A and eEF1Bα were not found in nuclei while all four subunits of eEF1H demonstrated both cytoplasmic and nuclear appearance in the lung carcinoma cell line A549. Unexpectedly, in the A549 nuclear fraction eEF1A lost the ability to interact with the eEF1B complex.ConclusionsThe results suggest independent functioning of some fraction of the eEF1H subunits in human tumors. The absence of eEF1A and eEF1B interplay in nuclei of A549 cells is a first evidence for non-translational role of nuclear-localized subunits of eEF1B. We conclude the appearance of the individual eEF1B subunits in tumors is a more general phenomenon than appreciated before and thus is a novel signal of cancer-related changes in translation apparatus.

Äîñë³äaeå íî çì³íè ê³ëüê³ñíî ãî ð³âíÿ ìî ëå êó ëÿð íî ãî øà ïå ðî íó Hsp60 ó òêà íèí³ ñåð öÿ ïðè äè ëÿ-òàö³éí³é êàðä³îì³îïàò³¿ (ÄÊÌÏ). Âè ÿâ ëå íî çðîñ òàí íÿ ñó ìàð íî ãî âì³ñòó Hsp60 ÿê ó ë³çà òàõ òêà íèíè ñåð äåöü ëþ äåé, õâî ðèõ íà ÄÊÌÏ, òàê ³ â ë³çà òàõ òêà íèí ñåð äåöü ìè øåé ³ç åê ñïå ðè ìåí òàëü íèì çà õâîðþ âàí íÿì, ïîä³áíèì äî ÄÊÌÏ ëþ äè íè. Âïåð øå âñòà íîâ ëå íî çá³ëüøåí íÿ ê³ëüêîñò³ Hsp60 ó ì³òî-õîíäð³àëüí³é ôðàêö³¿ òà çíè aeåí íÿ ó öè òîï ëàç ìà òè÷í³é, ùî ìîaeå áóòè îäíèì ³ç ÷èí íèê³â àïîï òî çó êàðä³îì³îöèò³â ïðè ñåð öåâ³é íå äîñ òàò íîñò³, âèê ëè êàí³é 䳺þ õðîí³÷íî ãî ñòðå ñó. Çà ðå çóëü òà òà ìè ³ìó íîã³ñòîõ³ì³÷íî ãî àíàë³çó ñåð äåöü ìè øåé ³ç åê ñïå ðè ìåí òàëü íîþ ïà òî ëî㳺þ, ïîä³áíîþ äî ÄÊÌÏ ëþ äè íè, ïî êà çà íî, ùî ï³äâè ùåí íÿ ê³ëüê³ñíî ãî ð³âíÿ Hsp60 ó òêà íèí³ ñåð öÿ íî ñèòü íå îäíîð³äíèé õàðàê òåð: çíà÷ íå çðîñ òàí íÿ â³äáó âàºòüñÿ ëèøå â îêðå ìèõ êàðä³îì³îöè òàõ, éìîâ³ðíî, â òèõ, äå àê òè âî-âàí³ àí òèñ òðå ñîâ³ ìå õàí³çìè çà õèñ òó êë³òèíè â³ä 䳿 õðîí³÷íî ãî ñòðå ñó. Êëþ ÷îâ³ ñëî âà: ìî ëå êó ëÿðí³ øà ïå ðî íè, Hsp60, äè ëÿ òàö³éíà êàðä³îì³îïàò³ÿ, êàðä³îì³îöèò, àïîï òîç.