In maize, immunoprecipitation assays have shown that CycD2;2 interacts with KRPs. However, evidence on CycD2;2 or KRPs localization and their possible interaction in specific tissues is lacking and ...its physiological consequence is still unknown. This work explores the spatiotemporal presence of CyclinD2s and KRPs, cell cycle regulators, during maize seed germination (18 and 36 h) after soaking on glucose or sucrose (120 mM). CyclinD2s are positive actors driving proliferation; KRPs are inhibitors of the main kinase controlling proliferation (a negative signal that slows down the cell cycle). Cell cycle proteins were analyzed by immunolocalization on longitudinal sections of maize embryo axis in seven different tissues or zones (with different proliferation or differentiation potential) and in the nucleus of their cells. Results showed a prevalence of these cell cycle proteins on embryo axes from dry seeds, particularly, their accumulation in nuclei of radicle cells. The absence of sugar caused the accumulation of these regulators in different proliferating zones. CyclinD2 abundance was reduced during germination in the presence of sucrose along the embryo axis, while there was an increase at 36 h on glucose. KRP proteins showed a slight increase at 18 h and a decrease at 36 h on both sugars. There was no correlation between cell cycle regulators/DNA co-localization on both sugars. Results suggest glucose induced a specific accumulation of each cell cycle regulator depending on the proliferation zone as well as nuclear localization which may reflect the differential morphogenetic program regarding the proliferation potential in each zone, while sucrose has a mild influence on both cell cycle proteins accumulation during germination. Whenever CycD2s were present in the nucleus, KRPs were absent after treatment with either sugar and at the two imbibition times analyzed, along the different embryo axe zones.
•In dry seeds of maize embryo axes, CycD2 localized outside the nucleus.•Glucose, but not sucrose, stimulates CycD2;2 accumulation at 36 h of germination.•KRP4;2 notably decreases along maize embryo axes on sugars at 18 and 36 h.•In the nucleus the localization of CycD2 and KRPs was mutually exclusive.•KRPs were excluded from the nucleus on sugar treatments.
The Glucose-Target of Rapamycin (Glc-TOR) pathway has been studied in different biological systems, but scarcely during early seed germination. This work examines its importance for cell ...proliferation, expression of cell cycle key genes, their protein levels, besides morphology and cellularization of the root apical meristem of maize (Zea mays) embryo axes during germination under the influence of two simple sugars, glucose and sucrose, and a specific inhibitor of TOR activity, AZD 8055. The two sugars promote germination similarly and to an extent, independently of TOR activity. However, the Glc-TOR pathway increases the number of cells committed to proliferation, increasing the expression of a cell cycle gene, ZmCycD4;2, a putative G1/S regulator. Also, Glc-TOR may have influence on the protein stability of another G1/S cyclin, ZmCycD3, but had no influence on ZmCDKA;1 or ZmKRP3 or their proteins. Results suggest that the Glc-TOR pathway participates in the regulation of proliferation through different mechanisms that, in the end, modify the timing of seed germination.
•Glucose-TOR participates on morphology determination of maize embryos axes.•Glucose-TOR pathway regulates expression of cell cycle related genes.•Glucose compromise more cells at RAM that Sucrose to proliferate via TOR.
•ZmPCNA, in structures of trimers and dimer of trimers associates to cell cycle proteins as CycD3;1, CDKs (A/B1;1) and KRPs.•Kinase activity identified in PCNA complexes is inhibited by cell cycle ...inhibitors as KRPs.•KRP1;1 and KRP4;2 inhibit differentially PCNA-associated kinase activity during the germination process.•PCNA acts as a platform congregating different cell cycle regulators at different physiological stages of maize germination.
The Proliferating Cell Nuclear Antigen, PCNA, has roles in both G1 and S phases of the cell cycle. Here we show that maize PCNA can be found in cells in structures of a trimer or a dimer of trimer, in complexes of high molecular mass that change in size as germination proceeds, co-eluting with cell cycle proteins as CycD3;1 and CDKs (A/B1;1). Using different methodological strategies, we show that PCNA actually interacts with CycD3;1, CDKA, CDKB1;1, KRP1;1 and KRP4;1, all of which contain PIP or PIP-like motifs. Anti-PCNA immunoprecipitates show kinase activity that is inhibited by KRP1;1 and KRP4;2, indicating the formation of quaternary complexes PCNA-CycD/CDKs-KRPs in which PCNA would act as a platform. This inhibitory effect seems to be differential during the germination process, more pronounced as germination advances, suggesting a complex regulatory mechanism in which PCNA could bind different sets of cyclins/CDKs, some more susceptible to inhibition by KRPs than others.
Smartphones took the world by storm in the 2000s. Over the years, smartphones have become vital in everyday life. Each generation responds to technology differently. The younger generation is much ...more involved with smartphones as well as technology as a whole. Thus, spending too much time on a smartphone could be related to individual’s well-being. The purpose of the present study is to measure Emotional Intelligence (EI), mindfulness, and social competence among different age cohorts and see if there are differences in phone use. Our hypothesis is that participants who score higher on EI, Social Skills, and Mindfulness will score lower on the Problematic Phone Usage Scale. Younger adults will score lower on EI, Social Skills, and Mindfulness and higher on Problematic Phone Usage than middle aged and older adults. We ran correlational analyses among, mindfulness, social competence, and problematic phone usage and an ex-post facto comparison between the four cohorts with ages ranging 18-30 (n=105), 31-40 years old (n= 30), 41-50 (n= 30), and 51 and older (n= 21). Survey questions included the Trait Emotional Intelligence Questionnaire- Short Form (TEIQ-SF), Kentucky Inventory of Mindfulness Skills, Social Competence, and Problematic Phone Usage Scale. Data showed that as age increased phone use decreased. EI, mindfulness, and social competence scores for younger adults were much lower than for middle aged and older adults while younger adults had a significantly larger problematic phone use than middle aged.
Glucose and sucrose play a dual role: as carbon and energy sources and as signaling molecules. In order to address the impact that sugars may have on maize seeds during germination, embryo axes were ...incubated with or without either of the two sugars. Expression of key cell cycle markers and protein abundance, cell patterning and de novo DNA synthesis in root meristem zones were analyzed. Embryo axes without added sugars in imbibition medium were unable to grow after 7 days; in sucrose, embryo axes developed seminal and primary roots with numerous root hairs, whereas in glucose axes showed a twisted morphology, no root hair formation but callus-like structures on adventitious and primary seminal roots. More and smaller cells were observed with glucose treatment in root apical meristems. de novo DNA synthesis was stimulated more by glucose than by sucrose. At 24 h of imbibition, expression of ZmCycD2;2a and ZmCycD4;2 was increased by sucrose and reduced by glucose. CDKA1;1 and CDKA2;1 expression was stimulated equally by both sugars. Protein abundance patterns were modified by sugars: ZmCycD2 showed peaks on glucose at 12 and 36 h of imbibition whereas sucrose promoted ZmCycD3 protein accumulation. In presence of glucose ZmCycD3, ZmCycD4 and ZmCycD6 protein abundance was reduced after 24 h. Finally, both sugars stimulated ZmCDKA protein accumulation but at different times. Overall, even though glucose appears to act as a stronger mitogen stimulator, sucrose stimulated the expression of more cell cycle markers during germination. This work provides evidence of a differential response of cell cycle markers to sucrose and glucose during maize germination that may affect the developmental program during plantlet establishment.
•Sucrose induced growth and differentiation during maize germination. Glucose acted as a mitogen.•Glucose-treated maize seedlings did not develop root hairs and instead formed callus-like structures.•Sucrose promoted accumulation of CycDs during late germination times.
During the postmenopausal period, there are metabolic alterations that predispose individuals to metabolic syndrome (MS), oxidative stress (OS), and the risk of developing cardiovascular diseases. We ...aimed to compare the concentrations of OS markers in postmenopausal women with and without MS. Malondialdehyde, carbonyl groups, and total antioxidant capacity (TAC) were quantified. We conducted a cross-sectional study: Group 1 (n = 42) included women without MS, and Group 2 (n = 58) comprised women with MS. Participants' age was similar between groups. Glucose, insulin, the homeostasis model assessment of insulin resistance, triglycerides, uric acid, and body mass index were significantly lower in postmenopausal women without MS. OS markers were significantly lower in Group 1 vs. Group 2: malondialdehyde, 31.32 ± 14.93 vs. 40.27 ± 17.62 pmol MDA/mg dry weight (p = .01); protein carbonylation, 6325 ± 1551 vs. 7163 ± 1029 pmol PC/mg protein (p = .0003); and TAC, 1497 ± 297.3 vs. 1619 ± 278.8 pmol Trolox equivalent/mg protein (p = .041). OS markers were significantly higher in postmenopausal women with MS.
Impact statement
What is already known on this subject? Oxidative stress has been implicated in numerous disease processes; however, information on the relationship between oxidative stress and metabolic syndrome among postmenopausal women remains limited.
What do the results of this study add? Our results indicate that in postmenopausal Mexican women, oxidative stress markers were significantly lower in those without metabolic syndrome, whereas total antioxidant capacity was higher in those with metabolic syndrome, which could be explained as an antioxidant defense mechanism capable of neutralising excess oxidative damage markers.
What are the implications of these findings for clinical practice and/or further research? This study is of interest to a broad audience because it compares the concentrations of oxidative stress markers in postmenopausal women with and without metabolic syndrome. Our study could support intervention with supplements or foods rich in antioxidants as lifestyle modifications in postmenopausal women with metabolic syndrome.
Oxidative damage present in obese/overweight mothers may lead to further oxidative stress conditions or inflammation in maternal and cord blood samples. Thirty-four pregnant women/newborn pairs were ...included in this study to assess the presence of oxidative stress biomarkers and their relationship with serum cytokine concentrations. Oxidative stress biomarkers and antioxidant enzymes were compared between the mother/offspring pairs. The presence of 27 cytokines was measured in maternal and cord blood samples. Analyses were initially performed between all mothers and newborns and later between normal weight and mothers with overweight and obesity, and diabetic/non-diabetic women.
Significant differences were found in biomarker concentrations between mothers and newborns. Additionally, superoxide-dismutase activity was higher in pre-pregnancy overweight mothers compared to those with normal weight. Activity for this enzyme was higher in neonates born from mothers with normal pregestational weight compared with their mothers. Nitrites in overweight/obese mothers were statistically lower than in their offspring. Maternal free fatty acids, nitrites, carbonylated proteins, malondialdehyde and superoxide dismutase predicted maternal serum concentrations of IL-4, IL-13, IP-10 and MIP-1β. Arginase activity in maternal plasma was related to decreased concentrations of IL-4 and IL-1β in cord arterial blood. Increased maternal malondialdehyde plasma was associated with higher levels of IL-6 and IL-7 in the offspring.
Oxidative stress biomarkers differ between mothers and offspring and can predict maternal and newborn cytokine concentrations, indicating a potential role for oxidative stress in foetal metabolic and immunologic programming. Moreover, maternal obesity and diabetes may affect maternal microenvironments, and oxidative stress related to these can have an impact on the placenta and foetal growth.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We have previously reported the expression of four different maize D cyclins during seed germination and showed that cytokinins and auxins stimulate the expression of every cyclin in a differential ...way. In this paper we characterize the behavior at the protein level of two of these cyclins, CycD5 and CycD4;1. Antibodies were raised against CycD5;2 (which very likely also recognizes D5;1) and CycD4;1 and Western blot studies demonstrated that neither BA nor indol-3 acetic acid (IAA) stimulate cyclin accumulation during germination, compared with control levels. However, phytohormones, particularly IAA, modify the kinase activity associated to D cyclins preferentially at early hours of germination. The associated kinase moiety to D cyclins appears to be of a Cdk-A type because this protein immunoprecipitates with D cyclins and because kinase activity is strongly inhibited by both olomoucine and also by a peptide corresponding to the carboxy end of a maize kip related protein (KRP) protein. There is thus no correlation between mRNA and protein expression for these maize D cyclins during seed germination, although phytohormones may stimulate a signaling cascade that stimulates activation of protein kinase activity in cyclin-Cdk complexes.
Background and Aims Childhood acute lymphoblastic leukemia (ALL) is the leading cause of childhood cancer-related deaths worldwide. Multiples studies have shown that ALL seems to be originated by an ...interaction between environmental and genetic susceptibility factors. The ARID5B polymorphisms are among the most reproducible ALL associated-risk alleles in different populations. The aim of the present study was to examine the contribution of ARID5B, CEBPE, and PIP4K2 risk alleles for the development of ALL in children from Mexico City and Yucatan, Mexico. Methods A study was conducted with a total of 761 unrelated subjects. Two hundred eighty five ALL cases (111 from Yucatan and 174 from Mexico City) and 476 healthy subjects. Genotyping included the rs7088318 ( PIP4K2A ), rs10821936 ( ARID5B ), rs7089424 ( ARID5B ) and rs2239633 ( CEBPE ) polymorphisms. Results Associations between ALL and rs10821936 and rs7089424 ARID5B SNPs were found (OR = 1.9, 95% CI (1.5–2.4) and OR = 2.0, 95% CI (1.6–2.5), respectively). Moreover, a higher risk was observed in the homozygous risk genotypes of carriers from Mexico City (OR = 3.1, 95% CI (2.0–4.9) and OR 3.1, CI 95% (2.0–4.8), respectively). Otherwise, the rs7088318 ( PIP4K2A ) and rs2239633 ( CEBPE ) polymorphisms were not associated with ALL risk. Conclusions Our analysis suggests that ARID5B confers risk for childhood ALL in a Mexican population.
Several different D-type cyclins can be found in plants and in maize, four of these have been characterized: CycD2;1, CycD4;1, CycD5;1 and CycD5;2. These cyclins appear to form complexes with Cdks, ...with PCNA and also with KRP proteins and in these kinase activity can be measured. The expression of the corresponding genes during maize germination is highly stimulated by phytohormones like auxin and cytokinin, however this is not followed by an equivalent increase in the amount of the corresponding proteins; nonetheless, auxins do stimulate the associated kinase activity, particularly at early germination times. Thus, auxins appear to stimulate the cell cycle during germination at two levels, transcription and kinase activation. Both auxins and cytokinins appear to shorten the G1 phase during germination and stimulate DNA synthesis, but apparently they do it in different ways as the simultaneous addition of both to germinating maize axes eliminates DNA synthesis stimulation. Therefore, similar actions may be achieved by different paths.
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