Statistical evaluation of chromosomes of some Lathyrus L. taxa growing in Turkey

In this study, statistical analysis was performed on mitotic metaphase chromosomes of 26 Lathyrus taxa, four of which are endemic. According to the findings obtained as a result of analysis, taxa close to each other were determined. Chromosome characteristics were revealed based on the arm lengths of taxa. Based on these, ANOVA, correlation analysis, PCA and cluster analysis were performed to determine the chromosomal relationships between taxa. Morphological similarities of plant taxa and chromosomal statistics results may not be always parallel to each other. According to Cluster Analysis, especially L. hirsutus - L. odoratus, L. brachypterus subsp. haussknechtii - L. phaselitanus, L. stenophyllus - L. chloranthus, L. gorgoni var. gorgoni, - L. nissolia - L. pratensis, L. tuberosus - L. annuus taxa are closely related.

Cluster analysis of karyotype similarity coefficients in Epimedium (Berberidaceae): insights in the systematics and evolution

In order to evaluate the genome evolution and systematics, karyotype analysis of mitotic metaphase chromosomes in 51 taxa of Epimedium and two species of Vancouveria was conducted. The 53 taxa were clustered, based on their karyotype similarity coefficients. Results showed that the 53 taxa studied were all diploid with 12 chromosomes (2n = 2x = 12). Each taxon had one pair of satellites located on pair I of homologous chromosomes. Moreover, the karyotype types of the 53 taxa studied were all type 1A or 2A of Stebbins. It can be concluded that the karyotypes between species are indeed very similar and the genome of Epimedium was conservative in evolution. The cluster analysis of karyotype similarity coefficients could provide valuable clues for the systematics and taxonomy of Epimedium. Results of the cluster analysis strongly supported the previous taxonomic division of E. subg. Rhizophyllum and E. subg. Epimedium. The results also showed that the interspecific relationship was closely correlated with geographical distribution in E. subg. Epimedium and the taxa native to east Asia had the highest genetic diversity in Epimedium. Finally, the origin of the modern geographical distribution of Epimedium was inferred. Results of the present study have significant scientific values in further studies on resource utilisation, taxonomy and phylogeny in Epimedium.

Physical Map of FISH 5S rDNA and (AG3T3)3 Signals Displays Chimonanthus campanulatus R.H. Chang & C.S. Ding Chromosomes, Reproduces its Metaphase Dynamics and Distinguishes Its Chromosomes

Chimonanthus campanulatus R.H. Chang & C.S. Ding is a good horticultural tree because of its beautiful yellow flowers and evergreen leaves. In this study, fluorescence in situ hybridization (FISH) was used to analyse mitotic metaphase chromosomes of Ch. campanulatus with 5S rDNA and (AG3T3)3 oligonucleotides. Twenty-two small chromosomes were observed. Weak 5S rDNA signals were observed only in proximal regions of two chromosomes, which were adjacent to the (AG3T3)3 proximal signals. Weak (AG3T3)3 signals were observed on both chromosome ends, which enabled accurate chromosome counts. A pair of satellite bodies was observed. (AG3T3)3 signals displayed quite high diversity, changing in intensity from weak to very strong as follows: far away from the chromosome ends (satellites), ends, subtelomeric regions, and proximal regions. Ten high-quality spreads revealed metaphase dynamics from the beginning to the end and the transition to anaphase. Chromosomes gradually grew larger and thicker into linked chromatids, which grew more significantly in width than in length. Based on the combination of 5S rDNA and (AG3T3)3 signal patterns, ten chromosomes were exclusively distinguished, and the remaining twelve chromosomes were divided into two distinct groups. Our physical map, which can reproduce dynamic metaphase progression and distinguish chromosomes, will powerfully guide cytogenetic research on Chimonanthus and other trees.

Identification of putative origin of Iris pumila L. karyotype

Aim. The study was aimed at cytogenetic analysis of Iris pumila, I. attica, and I. pseudopumila, comparative study of the karyotypes of these species, as well as identification of putative origin of I. pumila karyotype. Methods. Cytogenetic analysis of root apical meristem, determination of chromosome number in mitotic metaphase plates, anaphase analysis. Results. The chromosome numbers observed were 2n=32 for I. pumila plants from different localities in Ukraine and 2n=16 for I. attica and I. pseudopumila plants from Greece and Italy, respectively. Some of the plants were mixoploids, the smallest proportion of mixoploids was in I. pseudopumila (10.9%) and the largest in I.pumila from all studied populations (60-80%). Anaphase analysis showed the presence of chromosomal aberrations in 2.6% of cells in roots of I. pseudopumila seedlings. The highest level of structural chromosomal aberrations (9.2%) was found in root apical meristem cells of I. pumila seedlings. Conclusions. The chromosome number was established as 2n=32 for I.pumila plants and 2n=16 for I. attica and I. pseudopumila plants. The high level of mixoploidy (60–80% of mixoploid plants) and anaphase chromosomal aberrations (up to 9.2%) was found in apical meristem of I. pumila seedlings. The amphidipiloid nature of I. pumila was established; the karyotype of the species could be formed as a result of a combination of chromosome sets from hypothetical ancestral species I. attica and I. pseudopumila. Keywords: Iris pumila L., Iris attica Boiss. & Heldr., Iris pseudopumila Tineo, chromosome number, amphidiploid, mixoploidy.

FISH analysis of Zanthoxylum armatum based on oligonucleotides for 5S rDNA and (GAA)6

Fluorescence in situ hybridization (FISH) using oligonucleotide probes for (GAA)6 (18 bp) and ribosomal DNA (rDNA) (5S rDNA, 41 bp) was applied to analyse Zanthoxylum armatum. (GAA)6 loci were detected on the pericentromeric regions of five chromosome pairs, and 5S rDNA loci were also detected on the pericentromeric regions of another two chromosome pairs. The densities and locations of (GAA)6 and 5S rDNA signals varied between individual chromosomes. High-intensity (GAA)6 signals were detected at the centromeres of two large and two smaller metacentric chromosomes. Relatively strong (GAA)6 signals were detected at the centromeres of two relatively small metacentric chromosomes, although strong 5S rDNA signals were detected at the centromeres of two additional smaller metacentric chromosomes. Weak (GAA)6 signals were detected at the centromeres of four large metacentric chromosomes, whereas weak 5S rDNA signals were detected at the centromeres of two smaller metacentric chromosomes. The remaining chromosomes exhibited no signals. Zanthoxylum armatum had 2n = ∼128. The lengths of the mitotic metaphase chromosomes ranged from 1.22 to 2.34 μm. Our results provide information that may be beneficial for future cytogenetic studies and could contribute to the physical assembly of the Zanthoxylum genome.

Screening for Key Pathways Associated with the Development of Osteoporosis by Bioinformatics Analysis

Objectives.We aimed to find the key pathways associated with the development of osteoporosis.Methods.We downloaded expression profile data of GSE35959 and analyzed the differentially expressed genes (DEGs) in 3 comparison groups (old_op versus middle, old_op versus old, and old_op versus senescent). KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analyses were carried out. Besides, Venn diagram analysis and gene functional interaction (FI) network analysis were performed.Results.Totally 520 DEGs, 966 DEGs, and 709 DEGs were obtained in old_op versus middle, old_op versus old, and old_op versus senescent groups, respectively. Lysosome pathway was the significantly enriched pathways enriched by intersection genes. The pathways enriched by subnetwork modules suggested that mitotic metaphase and anaphase and signaling by Rho GTPases in module 1 had more proteins from module.Conclusions.Lysosome pathway, mitotic metaphase and anaphase, and signaling by Rho GTPases may be involved in the development of osteoporosis. Furthermore, Rho GTPases may regulate the balance of bone resorption and bone formation via controlling osteoclast and osteoblast. These 3 pathways may be regarded as the treatment targets for osteoporosis.

Heterochromatin and sibling species of Simulium praelargum s.l. (Diptera: Simuliidae)

Cytological descriptions are given for two sympatric sibling species, Simulium praelargum IIIL-st and Simulium praelargum IIIL-1.2, from Darjeeling, West Bengal, India. Sibling IIIL-1.2 differs from IIIL-st by a two step fixed included inversion (IIIL-1.2) found on the long arm of chromosome III. Both siblings possess heterochromatinized IIIS polytene chromosome ends, while IIIL-1.2 is unique within the Simuliidae in that it exhibits a very large enhanced chromocentre that persists in normal somatic tissue, contrary to other chromocentre-containing taxa. In IIIL-1.2, the chromocentre occurs as a positively allocyclic heteropycnotic body in normal mitotic interphase cells of neuroblast ganglia, oogonia, and spermatogonia. In mitotic metaphase chromosomes, the chromocentre forms large pronounced primary (centromere) constrictions and appears to be associated with nonhomologous pairing. Initial cytological studies on taxa within the feuerborni group have revealed heterochromatic chromosomal polymorphisms. Progressive fixation of these polymorphisms in different taxa within the group opens up the possibility of using comparative molecular or genomic approaches to begin to define the functional and structural aspects of the epigenome and to further characterize mitosis and meiosis in S. praelargum IIIL-1.2.