Yes-associated protein 1 (YAP1) is a transcriptional co-activator downstream of Hippo pathway. The pathway exerts crucial roles in organogenesis and its dysregulation is associated with the spreading of different cancer types. YAP1 gene encodes for multiple protein isoforms, whose specific functions are not well defined. We demonstrate the splicing of isoform-specific mRNAs is controlled in a stage- and tissue-specific fashion. We designed expression vectors encoding for the most-represented isoforms of YAP1 with either one or two WW domains and studied their specific signaling activities in YAP1 knock-out cell lines. YAP1 isoforms display both common and unique functions and activate distinct transcriptional programs, as the result of their unique protein interactomes. By generating TEAD-based transcriptional reporter cell lines, we demonstrate individual YAP1 isoforms display unique effects on cell proliferation and differentiation. Finally, we illustrate the complexity of the regulation of Hippo-YAP1 effector in physiological and in pathological conditions of the heart.

• Klíčová slova
• Alternative splicing, Cardiac differentiation, Tissue-specific expression, YAP1 isoforms,
• MeSH
• izoformy RNA * MeSH
• messenger RNA genetika   metabolismus   MeSH
• protein - isoformy genetika   metabolismus   MeSH
• proteiny buněčného cyklu * genetika   metabolismus   MeSH
• signální proteiny YAP MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• izoformy RNA * MeSH
• messenger RNA MeSH
• protein - isoformy MeSH
• proteiny buněčného cyklu * MeSH
• signální proteiny YAP MeSH

Metallothioneins (MTs) belong to a group of small cysteine-rich proteins that are ubiquitous throughout all kingdoms. The main function of MTs is scavenging of free radicals and detoxification and homeostating of heavy metals. In humans, 16 genes localized on chromosome 16 have been identified to encode four MT isoforms labelled by numbers (MT-1-MT-4). MT-2, MT-3 and MT-4 proteins are encoded by a single gene. MT-1 comprises many (sub)isoforms. The known active MT-1 genes are MT-1A, -1B, -1E, -1F, -1G, -1H, -1M and -1X. The rest of the MT-1 genes (MT-1C, -1D, -1I, -1J and -1L) are pseudogenes. The expression and localization of individual MT (sub)isoforms and pseudogenes vary at intra-cellular level and in individual tissues. Changes in MT expression are associated with the process of carcinogenesis of various types of human malignancies, or with a more aggressive phenotype and therapeutic resistance. Hence, MT (sub)isoform profiling status could be utilized for diagnostics and therapy of tumour diseases. This review aims on a comprehensive summary of methods for analysis of MTs at (sub)isoforms levels, their expression in single tumour diseases and strategies how this knowledge can be utilized in anticancer therapy.

• Klíčová slova
• Cancer, Diagnosis, Hypermethylation, Metallothioneins, Therapy,
• MeSH
• epigeneze genetická MeSH
• lidé MeSH
• metalothionein metabolismus   MeSH
• nádory farmakoterapie   genetika   metabolismus   MeSH
• protein - isoformy MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• metalothionein MeSH
• protein - isoformy MeSH

The p53 protein is a key tumor suppressor and the most commonly mutated and down-regulated protein in human tumors. It functions mainly through interaction with DNA, and p53 acts as a transcription factor that recognizes the so-called p53 target sites on the promoters of various genes. P53 has been shown to exist as many isoforms, including three C-terminal isoforms that are produced by alternative splicing. Because the C-terminal domain is responsible for sequence-nonspecific binding and regulation of p53 binding, we have analyzed DNA recognition by these C-terminal isoforms. Using atomic force microscopy, we show for the first time that all C-terminal isoforms recognize superhelical DNA. It is particularly noteworthy that a sequence-specific p53 consensus binding site is bound by p53α and β isoforms with similar affinities, whilst p53α shows higher binding to a quadruplex sequence than both p53β and p53γ, and p53γ loses preferential binding to both the consensus binding sequence and the quadruplex-forming sequence. These results show the important role of the variable p53 C-terminal amino acid sequences for DNA recognition.

• Klíčová slova
• Atomic force microscopy, G-quadruplex, Supercoiled DNA, p53 isoforms, p53-DNA binding,
• MeSH
• alternativní sestřih * MeSH
• DNA genetika   metabolismus   MeSH
• lidé MeSH
• nádorový supresorový protein p53 * metabolismus   MeSH
• protein - isoformy genetika   metabolismus   MeSH
• sekvence nukleotidů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DNA MeSH
• nádorový supresorový protein p53 * MeSH
• protein - isoformy MeSH

Apolipoprotein E (APOE) is distributed across various human tissues and plays a crucial role in lipid metabolism. Recent investigations have uncovered an additional facet of APOE's functionality, revealing its role in host defense against bacterial infections. To assess the antibacterial attributes of APOE3 and APOE4, we conducted antibacterial assays using Pseudomonas aeruginosa and Escherichia coli. Exploring the interaction between APOE isoforms and lipopolysaccharides (LPSs) from E. coli, we conducted several experiments, including gel shift assays, CD, and fluorescence spectroscopy. Furthermore, the interaction between APOE isoforms and LPS was further substantiated through atomic resolution molecular dynamics simulations. The presence of LPS induced the aggregation of APOE isoforms, a phenomenon confirmed through specific amyloid staining, as well as fluorescence and electron microscopy. The scavenging effects of APOE3/4 isoforms were studied through both in vitro and in vivo experiments. In summary, our study established that APOE isoforms exhibit binding to LPS, with a more pronounced affinity and complex formation observed for APOE4 compared with APOE3. Furthermore, our data suggest that APOE isoforms neutralize LPS through aggregation, leading to a reduction of local inflammation in experimental animal models. In addition, both isoforms demonstrated inhibitory effects on the growth of P. aeruginosa and E. coli. These findings provide new insights into the multifunctionality of APOE in the human body, particularly its role in innate immunity during bacterial infections.

• Klíčová slova
• antimicrobial peptides, apolipoprotein E isoforms, endotoxin, host defense, protein aggregation,
• MeSH
• apolipoprotein E3 * metabolismus   chemie   farmakologie   MeSH
• apolipoprotein E4 * metabolismus   chemie   farmakologie   MeSH
• Escherichia coli metabolismus   MeSH
• lidé MeSH
• lipopolysacharidy * metabolismus   chemie   MeSH
• myši MeSH
• protein - isoformy chemie   metabolismus   MeSH
• Pseudomonas aeruginosa metabolismus   MeSH
• simulace molekulární dynamiky MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• apolipoprotein E3 * MeSH
• apolipoprotein E4 * MeSH
• lipopolysacharidy * MeSH
• protein - isoformy MeSH

TP73 is a member of the TP53 gene family and produces N- and C-terminal protein isoforms through alternative promoters, alternative translation initiation and alternative splicing. Most notably, p73 protein isoforms may either contain a p53-like transactivation domain (TAp73 isoforms) or lack this domain (ΔTAp73 isoforms) and these variants have opposing or independent functions. To date, there is a lack of well-characterised isoform-specific p73 antibodies. Here, we produced polyclonal and monoclonal antibodies to N-terminal p73 variants and the C-terminal p73α isoform, the most common variant in human tissues. These reagents show that TAp73 is a marker of multiciliated epithelial cells, while ΔTAp73 is a marker of non-proliferative basal/reserve cells in squamous epithelium. We were unable to detect ΔNp73 variant proteins, in keeping with recent data that this is a minor form in human tissues. Most cervical squamous cell carcinomas (79%) express p73α, and the distribution of staining in basal cells correlated with lower tumour grade. TAp73 was found in 17% of these tumours, with a random distribution and no association with clinicopathological features. These data indicate roles for ΔTAp73 in maintaining a non-proliferative state of undifferentiated squamous epithelial cells and for TAp73 in the production of differentiated multiciliated cells.

• Klíčová slova
• Cervical cancer, Endometrium, Fallopian tube, Multiciliated cells, Squamous epithelial stem cells, p73 isoforms,
• MeSH
• epitelové buňky metabolismus   MeSH
• lidé MeSH
• monoklonální protilátky MeSH
• nádorové buněčné linie MeSH
• nádory děložního čípku metabolismus   patologie   genetika   MeSH
• nádory metabolismus   patologie   genetika   MeSH
• protein - isoformy * metabolismus   genetika   MeSH
• protein p73 * metabolismus   genetika   MeSH
• spinocelulární karcinom metabolismus   patologie   genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• delta Np73 protein, human MeSH Prohlížeč
• monoklonální protilátky MeSH
• protein - isoformy * MeSH
• protein p73 * MeSH
• TP73 protein, human MeSH Prohlížeč

Acute myeloid leukaemia (AML) is a complex haematological malignancy characterised by diverse genetic alterations leading to abnormal proliferation of myeloid precursor cells. One of the most significant genetic alterations in AML involves mutations in the FLT3 gene, which plays a critical role in haematopoiesis and haematopoietic homeostasis. This review explores the current understanding of FLT3 gene mutations and isoforms and the importance of the FLT3 protein in AML. FLT3 mutations, including internal tandem duplications (FLT3-ITD) and point mutations in the tyrosine kinase domain (FLT3-TKD), occur in 25-30% in AML and are associated with poor prognosis. FLT3-ITD mutations lead to constitutive activation of the FLT3 signalling pathway, promoting cell survival and proliferation. FLT3-TKD mutations affect the tyrosine kinase domain and affect AML prognosis in various ways. Furthermore, FLT3 isoforms, including shorter variants, contribute to the complexity of FLT3 biology. Additionally, nonpathological polymorphisms in FLT3 are being explored for their potential impact on AML prognosis and treatment response. This review also discusses the development of molecular treatments targeting FLT3, including first-generation and next-generation tyrosine kinase inhibitors, highlighting the challenges of resistance that often arise during therapy. The final chapter describes FLT3 protein domain rearrangements and their relevance to AML pathogenesis.

• Klíčová slova
• Acute myeloid leukaemia, FLT3, Gene isoforms, Mutations,
• MeSH
• akutní myeloidní leukemie * genetika   MeSH
• lidé MeSH
• mutace genetika   MeSH
• protein - isoformy genetika   MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• tyrosinkinasy MeSH
• viabilita buněk MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• FLT3 protein, human MeSH Prohlížeč
• protein - isoformy MeSH
• tyrosinkinasa 3 podobná fms MeSH
• tyrosinkinasy MeSH

Zinc-dependent histone deacetylases (HDACs) and sirtuins (SIRT) represent two different classes of enzymes which are responsible for deacylation of modified lysine side chains. The repertoire of acyl residues on lysine side chains identified in vivo is rapidly growing, and very recently lysine lactoylation was described to be involved in metabolic reprogramming. Additionally, lysine pyruvoylation represents a marker for aging and liver cirrhosis. Here, we report a systematic analysis of acyl-specificity of human zinc-dependent HDAC and sirtuin isoforms. We identified HDAC3 as a robust delactoylase with several-thousand-fold higher activity as compared to SIRT2, which was claimed to be the major in vivo delactoylase. Additionally, we systematically searched for enzymes, capable of removing pyruvoyl residues from lysine side chains. Using model peptides, we uncovered high depyruvoylase activity for HDAC6 and HDAC8. Interestingly, such substrates have extremely low KM values for both HDAC isoforms, pointing to possible in vivo functions.

• MeSH
• histondeacetylasy MeSH
• inhibitory histondeacetylas MeSH
• lidé MeSH
• lysin * chemie   MeSH
• protein - isoformy MeSH
• represorové proteiny metabolismus   MeSH
• sirtuin 2 * MeSH
• stárnutí MeSH
• zinek MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• systematický přehled MeSH
• Názvy látek
• HDAC8 protein, human MeSH Prohlížeč
• histondeacetylasy MeSH
• inhibitory histondeacetylas MeSH
• lysin * MeSH
• protein - isoformy MeSH
• represorové proteiny MeSH
• sirtuin 2 * MeSH
• zinek MeSH

LiCl/pilocarpine status epilepticus (SE) induced in immature rats leads, after a latent period, to hippocampal hyperexcitability. The excitability may be influenced by adenosine, which exhibits anticonvulsant activity. The concentration of adenosine is regulated by adenosine kinase (ADK) present in two isoforms-ADK-L and ADK-S. The main goal of the study is to elucidate the changes in ADK isoform expression after LiCl/pilocarpine SE and whether potential changes, as well as inhibition of ADK by 5-iodotubercidin (5-ITU), may contribute to changes in hippocampal excitability during brain development. LiCl/pilocarpine SE was elicited in 12-day-old rats. Hippocampal excitability in immature rats was studied by the model of hippocampal afterdischarges (ADs), in which we demonstrated the potential inhibitory effect of 5-ITU. ADs demonstrated significantly decreased hippocampal excitability 3 days after SE induction, whereas significant hyperexcitability after 20 days compared to controls was shown. 5-ITU administration showed its inhibitory effect on the ADs in 32-day-old SE rats compared to SE rats without 5-ITU. Moreover, both ADK isoforms were examined in the immature rat hippocampus. The ADK-L isoform demonstrated significantly decreased expression in 12-day-old SE rats compared to the appropriate naïve rats, whereas increased ADK-S isoform expression was revealed. A decreasing ADK-L/-S ratio showed the declining dominance of ADK-L isoform during early brain development. LiCl/pilocarpine SE increased the excitability of the hippocampus 20 days after SE induction. The ADK inhibitor 5-ITU exhibited anticonvulsant activity at the same age. Age-related differences in hippocampal excitability after SE might correspond to the development of ADK isoform levels in the hippocampus.

• Klíčová slova
• LiCl/pilocarpine, adenosine kinase, development, epileptic afterdischarges, hippocampus, inhibitor, isoforms, rat, status epilepticus,
• MeSH
• adenosin metabolismus   MeSH
• adenosinkinasa metabolismus   MeSH
• antikonvulziva farmakologie   MeSH
• hipokampus metabolismus   MeSH
• krysa rodu Rattus MeSH
• modely nemocí na zvířatech MeSH
• pilokarpin * toxicita   MeSH
• protein - isoformy metabolismus   MeSH
• status epilepticus * chemicky indukované   farmakoterapie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adenosin MeSH
• adenosinkinasa MeSH
• antikonvulziva MeSH
• pilokarpin * MeSH
• protein - isoformy MeSH

The objective of this study was to determine whether human auricular chondrocytes can also express alpha-- -smooth muscle actin. Immunohistochemistry using monoclonal antibodies for alpha-smooth actin, muscle-specific actin, beta-actin, S-100 protein, CD34, and desmin was performed on samples of human ear cartilage obtained from 20 individuals during a partial resection of the ear for different reasons. Moreover, the RT-PCR analysis of actin isoforms in auricular chondrocytes was performed. Approximately 60 % of the chondrocytes of the ear cartilage expressed alpha-smooth muscle actin as demonstrated by immunohistochemistry in all the examined samples. Actin-positive chondrocytes occurred in both external subperichondrial layers of the auricular cartilage. This finding was confirmed by the RT-PCR technique. The knowledge of this fact could help us to better understand the chondrocyte changes occurring during the healing and transplantation of auricular cartilage. The question of whether it is necessary to refer to these predominating cells in ear cartilage as myochondrocytes is considered. This is the first report of an unusual immunophenotype and contractile potential for human auricular chondrocytes.

• MeSH
• aktiny genetika   metabolismus   MeSH
• chondrocyty metabolismus   MeSH
• hladké svalstvo metabolismus   MeSH
• imunohistochemie MeSH
• lidé MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• protein - isoformy genetika   metabolismus   MeSH
• ušní chrupavka cytologie   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• aktiny MeSH
• protein - isoformy MeSH

Cellular senescence is a hallmark of normal aging and aging-related syndromes, including the premature aging disorder Hutchinson-Gilford Progeria Syndrome (HGPS), a rare genetic disorder caused by a single mutation in the LMNA gene that results in the constitutive expression of a truncated splicing mutant of lamin A known as progerin. Progerin accumulation leads to increased cellular stresses including unrepaired DNA damage, activation of the p53 signaling pathway and accelerated senescence. We previously established that the p53 isoforms ∆133p53 and p53β regulate senescence in normal human cells. However, their role in premature aging is unknown. Here we report that p53 isoforms are expressed in primary fibroblasts derived from HGPS patients, are associated with their accelerated senescence and that their manipulation can restore the replication capacity of HGPS fibroblasts. We found that in near-senescent HGPS fibroblasts, which exhibit low levels of ∆133p53 and high levels of p53β, restoration of Δ133p53 expression was sufficient to extend replicative lifespan and delay senescence, despite progerin levels and abnormal nuclear morphology remaining unchanged. Conversely, Δ133p53 depletion or p53β overexpression accelerated the onset of senescence in otherwise proliferative HGPS fibroblasts. Our data indicate that Δ133p53 exerts its role by modulating full-length p53 (FLp53) signaling to extend the replicative lifespan and promotes the repair of spontaneous progerin-induced DNA double-strand breaks (DSBs). We showed that Δ133p53 dominant-negative inhibition of FLp53 occurs directly at the p21/CDKN1A and miR-34a promoters, two p53 senescence-associated genes. In addition, Δ133p53 expression increased the expression of DNA repair RAD51, likely through upregulation of E2F1, a transcription factor that activates RAD51, to promote repair of DSBs. In summary, our data indicate that Δ133p53 modulates p53 signaling to repress progerin-induced early onset of senescence in HGPS cells. Therefore, restoration of ∆133p53 expression may be a novel therapeutic strategy to treat aging-associated phenotypes of HGPS in vivo.

• MeSH
• časové faktory MeSH
• fibroblasty patologie   fyziologie   MeSH
• kultivované buňky MeSH
• lidé MeSH
• nádorový supresorový protein p53 genetika   fyziologie   MeSH
• poškození DNA genetika   MeSH
• předčasné stárnutí genetika   patologie   MeSH
• progerie genetika   patologie   MeSH
• protein - isoformy fyziologie   MeSH
• stárnutí buněk genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• nádorový supresorový protein p53 MeSH
• protein - isoformy MeSH
• TP53 protein, human MeSH Prohlížeč