In plants, lipids serve as one of the major and vital cellular constituents. Neutral lipids reserves play an essential role in the plant life cycle by providing carbon and energy equivalents for periods of active metabol...In plants, lipids serve as one of the major and vital cellular constituents. Neutral lipids reserves play an essential role in the plant life cycle by providing carbon and energy equivalents for periods of active metabolism. The most common form of lipid storage are triacylglycerols (TAGs) packed into specialized organelles called lipid droplets (LDs). They have been observed in diverse plant organs and tissues, like oil seeds or pollen grains. LDs consist of a core, composed mostly of TAGs, enclosed by a single layer of phospholipids that is decorated by a unique set of structural proteins. Moreover, the recent advances in exploration of LDs proteome revealed a plethora of diverse proteins interacting with LDs. This is likely the result of a highly dynamic nature of these organelles and their involvement in many diverse aspect of cellular metabolism, tightly synchronized with plant developmental programs and directly related to plant-environment interactions. In this review we summarize and discuss the current progress in understanding the role of LDs and their cargo during plants life cycle, with a special emphasis on developmental aspects.
Epigenetic mechanisms, such as DNA methylation, RNA interference, posttranslational histone modifications and rearrangements of chromatin structure play an important role during genome reprogramming in both animals and p...Epigenetic mechanisms, such as DNA methylation, RNA interference, posttranslational histone modifications and rearrangements of chromatin structure play an important role during genome reprogramming in both animals and plants. The correct epigenetic pattern of eu- and heterochromatin marks allows for maintaining chromatin in an active or transcriptionally silenced state. In the life cycle of angiosperms, epigenetic mechanisms participate in genome reprogramming during: 1) differentiation of sporophyte cells into spore mother cells (SMC) that undergo meiosis, 2) development of female and male gametophytes, within which the gametes differentiate and 3) after double fertilization during the embryo and endosperm development. SMC speciation and control of meiosis, followed by reprogramming of the sperm cells and egg cell genome, are non-cell-autonomous and require RdDM pathway. These processes involve companion cells, which produce „mobile” siRNAs signal molecules. Epigenetic control of gene expression through siRNAs also participates in maintenance of gametes and embryo genome integrity and in the parental imprinting.
Depression is the most common mental illness, affecting approximately 350 million people around the world. Despite numerous studies, the etiology of this disease remains unclear. Previous studies suggest the involvement...Depression is the most common mental illness, affecting approximately 350 million people around the world. Despite numerous studies, the etiology of this disease remains unclear. Previous studies suggest the involvement of interrelated biochemical pathways, i.e. oxidative and nitrative stress as well as abnormalities of the tryptophan catabolites pathway (TRYCATs) in the depression development. Therefore, the aim of this study was to explain the role of oxidative and nitrative stress as well as disorders in the course of the TRYCATs pathway in the molecular basis of depression. In this study, an attempt was made to determine the effect of single nucleotide polymorphisms, located in genes, encoding enzymes involved in oxidative and nitrative stress, and the TRYCATs pathway on the incidence of depression. Moreover, using an in vivo model of depression, the impact of chronic mild stress stimuli on mRNA expression and protein amount as well as the degree of methylation of the promoter regions of genes encoding enzymes involved in the studied pathways was assessed. The obtained results clearly confirmed the studied biochemical pathways are involved in the development of depression at the molecular level.
During early gametogenesis the incomplete mitotic divisions occur. The cytokinesis is blocked and the sister cells do not fully separate. Instead, they stay connected via modified contractile rings known as stable interc...During early gametogenesis the incomplete mitotic divisions occur. The cytokinesis is blocked and the sister cells do not fully separate. Instead, they stay connected via modified contractile rings known as stable intercellular bridges or ring canals. Intercellular bridges are broad cytoplasmic strands (from 0,2μm to 20μm in diameter), which allow to exchange the gene products and organelles between interconnected cells. Such syncytial structures are termed germ-line cysts. As a rule, cysts are formed during spermatogenesis and they interconnect germ cells till sperm formation. In the female germ-line (oogenesis) cysts may not form at all, may be formed for a short period of time (till early meiosis) or may function till late oogenesis. Despite of universal mechanism of cysts formation (incomplete cytokinesis and bridge formation) there are substantial differences in cysts organization and functioning between taxa. The present paper gives the basic knowledge about formation and functioning of male and female germ-line cysts.
The Balbiani body is an organelle assemblage (termed sometimes a super-organelle) characteristic for the developing oocytes of almost all investigated animal species. In the vast majority of species, this complex resides...The Balbiani body is an organelle assemblage (termed sometimes a super-organelle) characteristic for the developing oocytes of almost all investigated animal species. In the vast majority of species, this complex resides next to the germinal vesicle and comprises such organelles as mitochondria, elements of endoplasmic reticulum, Golgi complexes as well as accumulations of nuage material. Comparative analyses have shown that the Balbiani bodies, even in closely related organisms, are often morphologically different. The differences concern not only the composition of this assemblage but also mutual relations between its components. So far, it has been found that the Balbiani body is implicated in several cellular processes undergoing in female germline cells. Most importantly this organelle complex is responsible for the delivery and localization of certain macromolecules and organelles to specific regions of the ooplasm (oocyte cytoplasm), as well as in the transfer of mitochondria to the zygote, i.e. to the next generation. Moreover, it has been shown recently that at least in some species the Balbiani body participates in the elimination of nonfunctional, damaged mitochondria from the developing oocytes and egg cells.
Skeletal muscles are a highly specialized animal tissue whose basic function is the contraction, which leads into animal movement. One of the types of skeletal muscles are trunk (myotomal) muscles, which in vertebrates b...Skeletal muscles are a highly specialized animal tissue whose basic function is the contraction, which leads into animal movement. One of the types of skeletal muscles are trunk (myotomal) muscles, which in vertebrates belong to the oldest phylogenetically group of muscles. The comparative studies of myotomal myogenesis have shown that these muscles, despite a similar structure plan and under the control of the same genetic factors, may differentiate differently in individual species of vertebrates (both in model and non-model species). The understanding of the skeletal muscle development mechanisms seem to be a precondition for understanding the muscle tissue diseases observed in humans. This paper summarizes the current knowledge on the skeletal muscles differentiation in animals, pathological states of muscles caused by mutations in the genes of structural and metabolic proteins.
The CHIMAERA has been known as a mythic, fire-breathing monster containing a lion’s head, goat’s body, and serpent’s tail. In modern biotechnology, this term has been used to describe organisms composed of cells derived...The CHIMAERA has been known as a mythic, fire-breathing monster containing a lion’s head, goat’s body, and serpent’s tail. In modern biotechnology, this term has been used to describe organisms composed of cells derived from at least two zygotes and thus differing genetically. Experimentally produced chimaeras have become an extremely valuable tool in biomedical research, used, among others, for investigating the developmental potential of cells, the differentiation processes that occur during embryogenesis, as well as for studying gene function, modelling human diseases, and developing new therapies. The interspecific chimaeras are also a promising approach for the generation of human organs for transplantation and saving endangered species. This article summarizes the current state of knowledge on chimaeras formed with the contribution of pluripotent stem cells and discusses the prospects and threats related to their use in basic research and medicine.
Bisphenol A is a monomeric organic compound belonging to phenols. It is widely used in the production of resins, polycarbonates and plastics. Mass production of this compound contributed to its widespread presence in the...Bisphenol A is a monomeric organic compound belonging to phenols. It is widely used in the production of resins, polycarbonates and plastics. Mass production of this compound contributed to its widespread presence in the environment, and thus - in the organisms of animals and humans. BPA belongs to xenoestrogens, synthetic compounds exerting an estrogen-like effect on cells. BPA can therefore disrupt the functioning of animal (including human) organisms. This article focuses on the impact of BPA on selected aspects of mammalian fertility. Recent literature data indicate that BPA disturbs several processes in oocytes and embryos, including epigenetic modifications, energy metabolism and spindle assembly, and as a result, decreases their developmental competence. We discuss the latest data on the influence of BPA on cellular processes taking place in oocytes and early embryos and describe molecular mechanisms responsible for this effect. We also discuss the significance of the results obtained from experiments conducted in vitro and/or on animal models in the context of BPA impact on fertility of women.
Developmental potential of oocytes and embryos is one of the key factors determining success in reproduction. In vitro produced embryos display reduced quality thus development of non-invasive approaches for quality asse...Developmental potential of oocytes and embryos is one of the key factors determining success in reproduction. In vitro produced embryos display reduced quality thus development of non-invasive approaches for quality assessment is a priority. Lipid metabolism belongs to fundamental mechanisms affecting reproductive processes and shaping the quality of gametes and embryos. The cytoplasm of oocytes and embryos contains specialized organelles for lipid storage (lipid droplets) whose number and size is species dependent. The growth and maturation of the oocyte/embryo is accompanied by a great fluctuation in lipid quality and quantity which in turn affects their quality and freezing suitability. There is a possibility to modify lipid parameters both in vivo and in vitro by supplementing fat to diet and culture media. The manuscript presents the current state of knowledge on lipid engagement in the process of quality acquirement by oocytes and embryos of two livestock species – cattle and pig.
Obtaining stable embryonic stem cells (ESC) from animals and humans opens up a wide spectrum of opportunities for science and regenerative medicine. The basic procedures necessary to obtain ESC are universal for all mamm...Obtaining stable embryonic stem cells (ESC) from animals and humans opens up a wide spectrum of opportunities for science and regenerative medicine. The basic procedures necessary to obtain ESC are universal for all mammalian species. The challenge is to maintain species specific conditions required to support pluripotency characteristic for the pre-implantation embryo. To date, true ESC lines (stable in culture, pluripotent with high differentiation potential) have been obtained only for a limited number of species such as, mice, human and rats. The main obstacles arise from species specific differences, and thus different environmental requirements. However, in all cases, it is essential to maintain the activity of pluripotency related signalling pathways (WNT, MAPK/ERK and JAK/STAT3). The classical system dedicated to obtain mouse and human ESCs dependant on LIF (mice) of FGF (human) is not optimal. Currently, ESC derivation systems are based on chemical inhibitors that have the ability to interact with the above-mentioned pathways. This manuscript introduces the key factors important for understanding the nature of various types of stem cells (not only those of embryonic origin), and explains why there is no one way to obtain pluripotency, and why the definition of a stem cell is not universal.
The assisted reproduction techniques are an essential part of endangered species conservation programs. All wild felids are threatened with extinction, and the domestic cat is a good and easily available model for resear...The assisted reproduction techniques are an essential part of endangered species conservation programs. All wild felids are threatened with extinction, and the domestic cat is a good and easily available model for research on wild felids. The procedures used in cats and wild felids include artificial insemination, oocytes collection from female and sperm collection from male, in vitro maturation of oocytes, in vitro fertilization by IVF and ICSI, embryo culture, embryo transfer, cryopreservation of gametes and embryos. The effectiveness of individual procedures in cats and wild felids is often much lower than in humans, livestock or laboratory animals, but the success achieved so far confirms the need for further research.
MicroRNAs (miRNAs), although do not encode proteins, they are involved in many biological processes. Here we focus on their role in skeletal muscle development and function. In health, they play an important role during...MicroRNAs (miRNAs), although do not encode proteins, they are involved in many biological processes. Here we focus on their role in skeletal muscle development and function. In health, they play an important role during skeletal muscle regeneration by regulating satellite cells quiescence, activation, proliferation, differentiation into myoblasts, and finally formation of myotubes. Moreover, miRNAs play a role in muscles disease development. For this reason, they can be used as disease biomarkers or potential therapeutic targets. Moreover, physical activity also influences the changes in miRNA expression. Certain types of exercises, their duration, and intensity differently impact the expression of many miRNAs.
Gametes are extremely differentiated cells participating in the fertilization to give the beginning of a new life. Except enabling fertilization, however, the fully functional gamete, should also guarantee full and undis...Gametes are extremely differentiated cells participating in the fertilization to give the beginning of a new life. Except enabling fertilization, however, the fully functional gamete, should also guarantee full and undisturbed development of the whole individual. The aim of this article is to approximate the mechanisms which occur during mammalian oogenesis which are crucial for ensuring the proper course of development as well as the quality of the genetic material transmitted to the progeny.
The embryonic development of placental mammals takes place inside the mother’s womb, which requires the formation of appropriate supportive structures by both the mother’s organism and the developing embryo. The first st...The embryonic development of placental mammals takes place inside the mother’s womb, which requires the formation of appropriate supportive structures by both the mother’s organism and the developing embryo. The first stages of mammalian embryonic development, preceding implantation, are the period of differentiation of the first cell lineages – epiblast (which will give rise to the embryo proper), and extra-embryonic lineages: trophectoderm (responsible for implantation and formation of the placenta) and primitive endoderm (giving rise to the yolk sac). Their differentiation is necessary for further development, and is a common feature of the development of all placental mammals, but the timing and molecular mechanisms responsible for these processes differ between mammalian species.
The sudden death of Professor Lech Wojtczak, the great Polish biochemist and a remarkable man, our Mentor and Friend, left us in sorrow and emptiness difficult to accept. Two years have passed already from this event and...The sudden death of Professor Lech Wojtczak, the great Polish biochemist and a remarkable man, our Mentor and Friend, left us in sorrow and emptiness difficult to accept. Two years have passed already from this event and our memories seem to be even more vivid, and his absence even more felt. Hence we decided to put on paper our personal reflections on Lech Wojtczak, each of us concentrating on a slightly different aspect of this towering figure. We tried to focus on memories and comments that were not mentioned in official obituaries that followed His passing away. Therefore do not expect to find here a comprehensive text on the Founder of Polish Bioenergetics, and a famous Polish biochemist, but rather a set of subjective comments on a man who made us scientists. Our memories are presented in a chronological order. The first chapter is by Professor Jolanta Barańska, who joined the group of Lech Wojtczak in 1968, followed by a chapter by Professor Maciej J. Nałęcz, who joined Lech in 1976, then Professor Konrad S. Famulski (1978) and finally followed by a chapter by Professor Adam Szewczyk, the youngest, joining the group in 1984.
Crossover is a reciprocal exchange of chromatid fragments between homologous chromosomes and takes place during second meiotic division. Many factors affect the distribution and frequency of crossovers – for instance, th...Crossover is a reciprocal exchange of chromatid fragments between homologous chromosomes and takes place during second meiotic division. Many factors affect the distribution and frequency of crossovers – for instance, the activity of trans-acting modifiers, chromatin methylation level or the presence of polymorphisms between recombining chromosomes. MMR system, and specifically MSH2 protein, serves to recognize and repair mismatched DNA bases, and prevents recombination between divergent chromosomal regions during meiosis. Unexpectedly, MSH2 displays also a pro-recombination role in plants by detecting polymorphisms and directing crossover events into more diverged regions. In this review, we demonstrate how interhomolog polymorphism may affect crossover chromosomal distribution and, as a consequence, plant genomes evolution. It is especially important for self-fertilizing plants which naturally exhibit high level of homozygosity. If recombination were to occur only in homozygous regions, no new genotypes would be created in subsequent generations, slowing down the evolution of the organisms.
Numerous studies indicate that dopamine (DA) is an important regulator of motor, psychological and cognitive functions. Maintaining the appropriate concentration of DA is a condition for the proper functioning of these f...Numerous studies indicate that dopamine (DA) is an important regulator of motor, psychological and cognitive functions. Maintaining the appropriate concentration of DA is a condition for the proper functioning of these functions. Tyrosine hydroxylase is involved in the control of DA synthesis. The aim of this study is to discuss the regulation of TH activity with the participation of three main mechanisms: 1) post-translational immediate regulation by phosphorylation of various sites in the enzyme molecule and 2) post-transcriptional with the participation of transcription factors and specific miRNAs, and 3) a DA mediated feedback mechanism. Important factors which are directly or indirectly involved in these regulations of TH activity and DA concentration are BDNF, testosterone, alpha-synuclein and protein kinases. A drastic reduction in DA levels in the extrapyramidal system causes drastic impairment of motor, psychological and cognitive functions. On the other hand, increased physical activity, in particular prolonged repetitive physical exercises by increasing the level of testosterone and BDNF in the blood, may activate signaling pathways dependent on them, increasing the activity of tyrosine hydroxylase, and thus increase the level of dopamine in the extrapyramidal system.
Lysosomal acid lipase (LAL) plays a key role in lipid metabolism through the hydrolysis of cholesteryl esters and triglycerides in lysosomes. LAL deficiency is a rare autosomal recessive lysosomal storage disease caused...Lysosomal acid lipase (LAL) plays a key role in lipid metabolism through the hydrolysis of cholesteryl esters and triglycerides in lysosomes. LAL deficiency is a rare autosomal recessive lysosomal storage disease caused by deleterious mutations in the LIPA gene. In the case of LAL deficiency, cholesteryl esters and triglycerides accumulate within the lysosomes. The up-regulation of endogenous cholesterol production, increased synthesis of apolipoprotein B (ApoB) and increased production of very-low-density lipoprotein cholesterol (VLDL-C) is observed. The diagnosis is easy due to the currently available method of testing the enzyme activity in a dry blood spot. Molecular analysis is necessary to verify the clinical and biochemical diagnosis and to analyze the genotype-phenotype correlation. Sebelipase alfa is a recombinant human lysosomal lipase intended for use in enzyme replacement therapy in patients with LAL deficiency.
MicroRNAs (miRNAs) are small single-stranded molecules of RNA (21-23 nucleotides) which regulate the expression of different genes on a posttranscriptional level through binding to mRNA. miRNA regulate a number of biolog...MicroRNAs (miRNAs) are small single-stranded molecules of RNA (21-23 nucleotides) which regulate the expression of different genes on a posttranscriptional level through binding to mRNA. miRNA regulate a number of biological processes such as: proliferation, differentiation, angiogenesis, migration, apoptosis or oncogenesis. Many studies have proved involvement of miRNA in cancer progression from its initial stage to metastasis. Wide range of genes regulated by miRNA in the course of the cancer disease allowed to distinguish two classes of miRNA: suppressors and oncomirs. Monitoring the changes in expression profile of chosen miRNA could help in early identification of cancer cells and serve as a prediction factor of the disease or treatment. Defining target genes of deregulated miRNA in cancer cells and developing methods of their selective silencing is a promising therapeutic strategy. This paper presents selected studies focused on the use of miRNA as a diagnostic marker and a potential target of modern cancer therapies.
Plants are natural laboratories producing a cornucopia of secondary metabolites of huge therapeutic potential. The oil extracted from rice bran, a by-product of brown rice processing, is abundant in valuable bioactive su...Plants are natural laboratories producing a cornucopia of secondary metabolites of huge therapeutic potential. The oil extracted from rice bran, a by-product of brown rice processing, is abundant in valuable bioactive substances. One of its main ingredients is gamma-oryzanol that is a mixture of phytosterol esters and ferulic acid. These compounds exert a wide range of biological activities closely correlated with their chemical properties. Their hypocholesterolemic and antioxidant abilities are crucial for improving the physiology and condition of the human body. For these reasons, there has been a clear increase in the number of studies investigating the use of gamma-oryzanol in the treatment of many chronic diseases, and it is even tested as a promising non-pharmacological therapeutic agent in the treatment of COVID-19 in overweight people. This paper describes the chemical structure and activity of gamma-oryzanol based on biological activity of phytosterol esters and ferulic acid. It also discusses the effects of gamma-oryzanol on some physiological processes in the human and animal organisms.