chromosomal number
Recently Published Documents


TOTAL DOCUMENTS

28
(FIVE YEARS 2)

H-INDEX

7
(FIVE YEARS 0)

2021 ◽  
Vol 69 (2) ◽  
pp. 93-99
Author(s):  
Yavuz Koçak ◽  
Elmas Yağmur

Information on the karyotypes of Turkish species of Cerambycidae is scanty. Our study contributes to the knowledge of the karyological data (chromosomal number and mechanism of sex determination) of five Turkish longicorn beetles; karyotypes of four taxa, one endemic, are described for the first time and for the remaining one, Purpuricenus budensis (Götz, 1783), the previously published chromosome count is confirmed. The chromosome number of Purpuricenus desfontainii inhumeralis Pic, 1891 and Purpuricenus budensis (Götz, 1783) (Cerambycinae, Trachyderini) was found to be 2n = 28 (13 + Xyp); Clytus rhamni Germar, 1817 and Plagionotus floralis (Pallas, 1773) (Cerambycinae, Clytini) 2n = 20 (9 + Xyp); and the endemic Dorcadion triste phrygicum Peks, 1993 (Lamiinae, Dorcadionini) 2n = 24 (11 + Xyp). In view of the paucity of data available until now, our study is important for both to improve the poor karyological knowledge of Turkish Cerambycidae and to provide an incentive for other researchers.


Author(s):  
Musafer H. Al-Ardi

Entamoeba histolytica, like other Organismes, is characterized by diversity and heterogeneity in its genetic content, which is one of the most important reasons for survival, and the increase in susceptibility to infection.Non-condensation of chromosomes during the process of cell division and the ambiguity of the chromosomal ploidy makes predicting the exact chromosomal number difficult. Genes distributed across 14 chromosomes as well as many extra-chromosome elements. Most Genes composed of one axon only, with Introns in 25% of Genes. This genome is characterized by the presence of Polymorphic internal repeat regions, and several gene families, one of these large families encoding Transmembrane kinas, Cysteine protease (CP), SREHP protein, and others.


2019 ◽  
pp. 55-62

Micropropagación y determinación cromosómica del género Croton productores de látex Micropropagation and chromosomal determination of the latex producing gender Croton Astriht Ruiz Ríos y María de Lourdes Tapia y Figueroa Universidad Nacional de San Martín-Tarapoto, Jr. Dos de Mayo N°340, Moyobamba, perú Universidad Nacional Agraria, La Molina, Lima, perú DOI: https://doi.org/10.33017/RevECIPeru2010.0021/ RESUMEN El presente trabajo de investigación tuvo como objetivos: determinar las diferencias en el desarrollo in vitro de yemas provenientes de plantas juveniles de croton productores de látex; evaluar la respuesta a la aclimatación de plántulas de croton de mejor comportamiento in vitro y determinar el número cromosómico de individuos seleccionados del género croton productores de látex. El medio de cultivo para la introducción in vitro fue determinado evaluando el comportamiento de croton draconoides en cinco tratamientos cuyo medio básico fue el de Murashige y Skoog (MS) tomando en consideración que las especies en estudio pertenecen al mismo género. Las yemas provenientes de plantas juveniles de croton productor de látex color vino fueron las que mejor comportamiento tuvieron en el medio de cultivo seleccionado (MS + 0,01mg/l de ANA + 0,1 mg/l de BAp y AG3 + 20 ml de agua de coco), presentando mayor altura, número de hojas y porcentaje de sobrevivencia en relación a croton productor de látex color rojo y ocre. Las plántulas de croton productor de látex color vino, previamente enraizadas in vitro, fueron llevadas a aclimatación, probando cuatro substratos, determinándose que las respuestas de las plántulas varían de acuerdo a la composición del sustrato, las condiciones de riego (nebulización), el control de hongos (benlate al 0.1%) y la aplicación del bioestimulante biogen 1 al 0,1%. El número cromosómico determinado en las plantas del género croton productoras de látex rojo, vino y ocre fue de 40. Descriptores: croton, látex, in vitro, micropropagación, plántulas, explantes. ABSTRACT The present investigation had the purpose of: determining the differences in the in vitro development of buds from croton young plants of latex producers; to evaluate the response to the acclimatization of croton’s plantulas with better behavior in vitro, and to determine the chromosomal number of selected individuals of croton latex producers. The culture medium for the in vitro introduction was determined evaluating the behavior of croton draconoides in five treatments with the basic medium murashige and skoog (ms) taking into consideration that the species in the study belong to the same gender. The buds coming from croton young plants producers of wine latex had the best behavior in the selected culture medium (ms + 0,01mg/i ana + 0,1mg/i of baP and aG3 + 20 ml of coconut water) presenting an increase in height, number of leaves and percentage of survival in relationship to croton producers of red and ocher latex. The plantulas of croton producers of wine latex, previously rooted in vitro, were taken for acclimatization. Four substrates were tested, determining that the response of the plantulas changes according to the substrate composition, watering conditions (nebulization), fungus control (benlate to 0,1%) and the application of the bioestimulant biogen 1 to 0,1%. The chromosomal number determined in plants of the gender croton producers of red, wine and ocher latex was of 40. Keywords: croton, latex, in vitro, micropropagation, seedlings, explants.


Cells divide for three main reasons: growth and development, replace worn-out or injured cells, and reproduction of offspring. Cell division is part of the cell cycle divided into five distinct phases. The diploid state of the cell is the normal chromosomal number in species. During sexual reproduction, the cell's chromosome number is reduced to a haploid state to ensure constancy in chromosome number and thus continuation of the species. The process of cell division is controlled by regulatory proteins. Mitosis occurs in all body cells and is divided into four phases. Meiosis, which occurs in only the germ cells involved in reproduction, divides the chromosomes in two rounds termed meiosis I and meiosis II (reduction division). The human lifecycle starts with gametogenesis, the process that forms gametes which then combine to form a zygote. The zygote quickly becomes an embryo and develops rapidly into a foetus. This chapter explores cell division.


2016 ◽  
Vol 25 (2) ◽  
pp. 233-238 ◽  
Author(s):  
I.A. Gavrilov-Zimin ◽  
D.A. Gapon

Two Afrotropical scale insect species, Trochiscococcus speciosus (De Lotto, 1961) and Ripersiella aloes (Williams et Pellizzari, 1997), are recorded for the first time in Russia, St Petersburg, under glass on the roots of Gasteria sp. (Asphodelaceae). The first species is morphologically described and illustrated by a standard total coccidological figure and by the photograph; a study of the reproductive biology of this species revealed an obligate ovoviviparity, parthenogenesis (thelytoky) and the chromosomal number 2n=10. The quarantine status for both species is advised on the territory of Russia and neighbouring countries.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 280-280 ◽  
Author(s):  
Ernesto Diaz-Flores ◽  
Evan Q. Comeaux ◽  
Kailyn Kim ◽  
Kyle Beckman ◽  
Kara L. Davis ◽  
...  

Abstract Acute lymphoblastic leukemia (ALL) is the most common cancer of childhood. Specific genetic subsets, including hypodiploid ALL, are associated with particularly high rates of relapse. Despite the poor outcomes of hypodiploid B-ALL with traditional therapeutic approaches, there have been no known effective alternative therapies or novel candidates tested to improve outcome. We hypothesized that new therapeutic targets could by identified by integrated biochemical and genomic profiling, combined with functional drug assays in order to determine which pathways play an essential role in transformation. For biochemical profiling, we analyzed multiple pathways commonly deregulated in leukemias using phosphoflowcytometry (including receptor tyrosine kinases, JAK/STAT, MAPK, PI3K, PTEN, Bcl-2 survival and pro-apoptotic family members and p53). We subjected hypodiploid cell lines (NALM-16, MHH-CALL2) and patient derived xenograft samples in vitro to inhibitors against each of these pathways (PP2:Src family;Ruxolitinib: JAK/STAT; PD235901/CI1040: MAPK; GDC-0941, PI-90, PI-103, p110 (a, b, g, d): PI3K isoform specific; PP-242:mTOR; ABT-263/ABT-737: Bcl-2/Bcl-xl, and ABT-199: Bcl-2 specific). We found that the Bcl-2 inhibitors (ABT-263, ABT-737 and ABT-199) and to a lesser extent PI3K pathway inhibitors GDC-0941 and PP-242, but not the MAPK or RTK inhibitors, efficiently reduced proliferation of hypodiploid cells. However, only ABT-263/ABT-199 induced high levels of apoptosis at nanomolar concentrations. Based on the consistent efficacy observed with ABT-199 against hypodiploid patient-derived cells and cell lines in culture, we selected eight cryopreserved, previously xenografted (F3 generation) hypodiploid patient samples (4 low hypodiploid, chromosomal number between 32 and 39; and 4 Near Haploid, chromosomal number between 24 and 31) and three non-hypodiploid patient samples (Ph-positive,Ph-Like and Erg+) for a preclinical trial in immunodeficient mice. Each patient sample was engrafted into six mice, which were randomized to receive vehicle or ABT-199 daily over 60 days (Figure 1). Treatment started when the peripheral blood (PB) human CD45 count reached 15%. A rapid decrease in PB blasts was noted at 7 days (Figure 1). Eighty-five percent of the hypodiploid xenografts survived 60 days with either undetectable or low levels of leukemia in the PB. In contrastPh+ andPh-Like xenografts died within 10-20 days regardless of treatment. Importantly, hypodiploid leukemic blasts gradually emerged after discontinuing ABT-199 after 60 days. Additionally, despite low or undetectable levels of leukemic blasts in PB and reduced levels in bone marrow and spleen, all mice had high percentages of leukemic cells in the liver (Figure 2). In conclusion we have identified the survival protein Bcl-2 as a promising molecular target in hypodiploid B-ALL. ABT-199 for dramatically reduced leukemia cells in vitro and in vivo in patient-derived xenograft models of hypodiploid B-ALL. However, the liver represented a protective niche for these leukemias. In addition, our biochemical characterization of the organ infiltrating blasts collected from mice on trial indicate that the sensitivity of hypodiploid ALL to ABT-199 relies not only on high levels of Bcl-2 and deficiency for other survival proteins such as Bcl-xl but also on high levels of proapoptotic proteins, providing two different signatures that correlate with response to ABT-199. Using genome editing (CRISPR/Cas9) we interrogated the necessity for individual proapoptotic genes, including PUMA, NOXA, and BAD, for ABT-199-induced cell death. This study provides encouraging preclinical data that Bcl-2 may be a promising target for the treatment of hypodiploid B-ALL. Our studies identify signature biomarkers that correlate with drug response and identify essential proteins mediating ABT-199-induced cell death. Importantly, this report also identifies the limitations of using ABT-199 as single drug, and provides the rationale for using combinatorial therapies in order to improve the efficacy of the drug. Disclosures Mullighan: Loxo Oncology: Research Funding; Amgen: Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees. Loh:Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Abbvie: Research Funding.


2015 ◽  
Vol 147 (1) ◽  
pp. 48-54 ◽  
Author(s):  
Michail Rovatsos ◽  
Martina Johnson Pokorná ◽  
Lukáš Kratochvíl

Highly differentiated heteromorphic ZZ/ZW sex chromosomes with a heterochromatic W are a basic principle among advanced snakes of the lineage Colubroidea, while other snake lineages generally lack these characteristics. For the first time, we cytogenetically examined the dragonsnake, Xenodermus javanicus, a member of the family Xenodermatidae, which is phylogenetically nested between snake lineages with and without differentiated sex chromosomes. Although most snakes have a karyotype with a stable chromosomal number of 2n = 36, the dragonsnake has an unusual, derived karyotype with 2n = 32 chromosomes. We found that heteromorphic ZZ/ZW sex chromosomes with a heterochromatic W are present in the dragonsnake, which suggests that the emergence of a highly differentiated W sex chromosome within snakes predates the split of Xenodermatidae and the clade including families Pareatidae, Viperidae, Homalopsidae, Lamprophiidae, Elapidae, and Colubridae. Although accumulations of interstitial telomeric sequences have not been previously reported in snakes, by using FISH with a telomeric probe we discovered them in 6 pairs of autosomes as well as in the W sex chromosome of the dragonsnake. Similarly to advanced snakes, the sex chromosomes of the dragonsnake have a significant accumulation of repeats containing a (GATA)n sequence. The results facilitate the dating of the differentiation of sex chromosomes within snakes back to the split between Xenodermatidae and other advanced snakes, i.e. around 40-75 mya.


2014 ◽  
Vol 32 (15_suppl) ◽  
pp. 6072-6072 ◽  
Author(s):  
Howard B. Urnovitz ◽  
Julia Beck ◽  
Kirsten Bornemann-Kolatzki ◽  
Brent E Richardson ◽  
John H Lee ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document