Fragment of the gene encoding chymotrypsin and trypsin inhibitor protein of potato tubers

Product of polymerase chain reaction designated as PKPIJ-B was isolated after amplification from genomic DNA of potato (Solarium tuberosum L., Zhukov Jubilee cultivar) using the designed primers. Nucleotide sequence of PKPIJ-B was determined and amino acid sequence of protein was restored. Analysis of this sequence has allowed us to suggest that isolated gene fragment encodes chymotrypsin and trypsin inhibitor protein (PKCI-23 potato Kunitz-type chymotrypsin inhibitor) of potato tubers.     

Characteristics of karyosphere formation in the lake frog. Light microscopy data

Morphological peculiarities of the oocyte nuclear organization were examined in R. ridibunda during winter and spring (February-March). Numerous nucleoli were seen to be assembled around regressive lampbrush chromosomes in the centre of the nucleus, and a central body was formed to which the chromosomes were attached. As result, a structural complex is constituted that involves a karyosphere and a capsule. Nucleoli are characterized by segregation and intensive fragmentation of their material. In result, a considerable part of nucleolar DNA is eliminated in the form of ring and polymorphous structures (micronucleoli). Besides the membranous component of nucleoli (nucleolar threads or tails) is lost. Towards the end of this period, nucleoli with complicated morphology become spherical again. The formation of the central body is started from the appearance of some small optically-light protein structures 5-20 nm in diameter (central body precursors-CBP). CBP are closely surrounded with ring micronucleoli to make intimate contact with the chromosomes and nucleolar threads. CBP commonly lie in one region of the nucleus not far from each other. The formation of a definitive central body obviously occurs due to a fusion of some small CBP. A conclusion is made of the nucleolar origin of the ring and polymorphous structures and of their essential role in the central body formation. The participation of chromosomal and eliminated nucleolar DNA in this process is discussed.     

Nuclear structures in the late oogenesis of Rana temporaria. III. Electron microscopic studies]

The ultrastructural organization of the vitellogenic oocyte nucleus (stage VI, according to Duryee, 1950) was studied in normal and in vitro hormone-stimulated maturing oocytes of Rana temporaria. At this stage, numerous nucleoli are gathered around the knot of highly contracted chromosomes (the karyosphere) thus making the karyosphere capsule. Light microscope observations reveal three zones in the capsule: a central fibrous zone separating the chromosomes from the nucleoli, a middle zone, consisting of numerous nucleoli and a distinct fibrous componen; in addition a fibrous zone on the capsule periphery is seen. The nucleoli are fibrillar, bear no proribosomal granules and do not synthesize RNA. This period is characterized by an intensive fragmentation and segregation of the nucleolar material. Numerous micronucleoli and nuclear bodies occur in the nucleus. The nucleoli are normally compound and irregular in shape to become spherical in hormone-stimulated maturing oocytes. In the central fibrous zone of the capsule, separating the chromosomes from the nucleoli, some peculiar abundant accumulations of annuli were detected lacking the membranes component. Annuli are linked with the fibrous material and are regularily packed making peculiar pseudomembranes (PMM). The chromatin is connected with PMM directly. In the middle zone of the capsule, accumulations of PMM are also seen, though less abundant and less regularly packed; along with annuli, membranous areas of various size and form are met in PMM. PMM are connected with the micronucleoli with filaments 20 nm thick. In the peripheral zone of the capsule, a variety of membranous structures is detected: intranuclear annuli lamellae, component of the capsule consists of different membranous and pseudomembranous (with annuli) structures. A question of the contribution of the chromatin material in the formation of the fibrous capsular component (PMM and membranous structures) is discussed.     

“Double” Pyrimidine Derivatives: Synthesis and Primary Assessment of Hepatoprotective Properties In Vitro

Russian Journal of Bioorganic Chemistry - “Double” derivatives of the drug Xymedon (1,2-dihydro-4,6-dimethyl-1-N-(hydroxyethyl)pyrimidone-2), hereafter referred to as pyrimidine (I), in...     

Cellular aspects of pathogenesis of hypertrophic cardiomyopathy: Role of cardiomyocyte polyploidy and activation of nuclear antigen of the proliferating cell in myocardium

For a comparative analysis of cytomorphological characteristics of hypertrophied interventricular septum (IVS), both patients different ages with severe courses of obstructive hypertrophic cardiomyopathy (OHCMP) were examined, including children, and patients with essential arterial hypertension (EAH). The course of OHCMP in children as compared with adults was found to be characterized by considerable IVS hypertrophy that was accompanied by an acceleration of cardiomyocyte polyploidization. The mean ploidy level of cardiomyocytes in children with OHCMP was higher than in adult patients. The mean ploidy level of nuclei, the number of prolipherative cell nuclear antigen (PCNA)-positive nuclei, and the number of polyploid cardiomyocyte nuclei in adult patients with OHCMP were significantly higher statistically than in patients with EAH. The PCNA-positive labels in stromal cells were revealed only in patients with OHCMP. The obtained data indicate an important role of cardiomyocyte polyploidy and of activation of the proliferating cell nuclear antigen in development of myocardial hypertrophy in patients with OHCMP.     

Distribution of RNA polymerase II in nuclei of early murine embryos

Nuclear distribution of unphosphorylated and phosphorylated forms of RNA polymerase II in two celled mouse embryos was studied using immunoelectron microscopy. RNA polymerase II was shown to be present in the karyoplasm of mouse embryo nuclei at the early two-celled stage, that is before activation of the embryonic genome. During this period, RNA polymerase II is diffusely localized in the nuclei being not associated with any nuclear domains. After embryonic genome activation, the pattern of the nuclear distribution of RNA polymerase II is changed. At the late two-celled stage, its prominent part is deposited in pronucleoli, as well as in interchromatin granule clusters and perichromatin fibrils. At this stage, unphosphorylated RNA polymerase II is mainly associated with perichromatin fibrils. The obtained data fit well with the notion of the coordinated distribution of RNA polymerase II and splicing factors, and of their association with the same nuclear domains.