ABSTRACT
Objective@#To investigate the current status of myopia in children and adolescents in Qamdo, Tibet, and analyze related influencing factors, so as to provide a basis for the prevention and control of adolescents in plateau areas.@*Methods@#A cross sectional study was conducted among 959 children and adolescents randomly selected from one district and two counties in Qamdo (from the fourth grade of elementary school to the second grade of high school) for visual acuity and refraction tests and filled out a vision related behavior questionnaire to analyze the incidence of myopia among adolescents in the region and its associated factors.@*Results@#The myopia rate of adolescents in grades 4-11 was 54.43%, the rate of undercorrection of refractive errors was 85.25%, and the percentage of students wearing eyeglasses was 34.67%,fully vision correction rate was 42.54%. The myopia rate of students in grades 4-6 was 35.14%, 64.71% in grades 7-9, and 73.48% in grades 10-11. The myopia rate increased with grades( χ 2= 101.18 , P <0.01). The myopia rate (70.40%) of urban students (grades 4-9) was higher than that of county level(41.45%), and the myopia rate of students with myopia from either parent (68.24%) was higher than that of students without myopia (51.91%) , the myopia rate of girls (59.96%) was higher than that of boys (48.36%)( χ 2=53.19，13.46，12.98， P <0.01). Use electronic products for more than 2.5 hours per day, electronic devices usage after bedtime, the light low indoor brightness when studying on a sunny day, and only use one of the table lamps or roof lights when studying at night, preference for fried food, poor sleep quality, in the morning the students who still feel tired are at higher risk of myopia( χ 2=10.35, 10.91, 6.87, 4.25, 4.97, 5.71, 12.11, P < 0.05). Multivariate regression analysis showed that the occurrence of myopia was related to region, grade, gender, parental myopia, time spent on electronic products every day in the past 5 months, and sleep quality( P <0.05).@*Conclusion@#The high rate of myopia in children and adolescents in Qamdo may be related to the quality of sleep, the length of time electronic products are used, the eye environment, and the frequency of eating fried foods. Outdoor activities do not show significant differences.
ABSTRACT
SWEET proteins play an indispensable role as a sugar efflux transporter in plant development and stress responses. The SWEET genes have previously been characterized in several plants. Here, we present a comprehensive analysis of this gene family in the rubber tree, Hevea brasiliensis. There are 36 members of the SWEET gene family in this species, making it one of the largest families in plant genomes sequenced so far. Structure and phylogeny analyses of these genes in Hevea and in other species demonstrated broad evolutionary conservation. RNA-seq analyses revealed that SWEET2, 16, and 17 might represent the main evolutionary direction of SWEET genes in plants. Our results in Hevea suggested the involvement of HbSWEET1a, 2e, 2f, and 3b in phloem loading, HbSWEET10a and 16b in laticifer sugar transport, and HbSWEET9a in nectary-specific sugar transport. Parallel studies of RNA-seq analyses extended to three other plant species (Manihot esculenta, Populus trichocarpa, and Arabidopsis thaliana) produced findings which implicated MeSWEET10a, 3a, and 15b in M. esculenta storage root development, and the involvement of PtSWEET16b and PtSWEET16d in P. trichocarpa xylem development. RT-qPCR results further revealed that HbSWEET10a, 16b, and 1a play important roles in phloem sugar transport. The results from this study provide a foundation not only for further investigation into the functionality of the SWEET gene family in Hevea, especially in its sugar transport for latex production, but also for related studies of this gene family in the plant kingdom.
ABSTRACT
Calcium-dependent protein kinases (CDPKs or CPKs) play important roles in various physiological processes of plants, including growth and development, stress responses and hormone signaling. Although the CDPK gene family has been characterized in several model plants, little is known about this gene family in Hevea brasiliensis (the Para rubber tree). Here, we characterize the entire H. brasiliensis CDPK and CDPK-related kinase (CRK) gene families comprising 30 CDPK genes (HbCPK1 to 30) and nine CRK genes (HbCRK1 to 9). Structure and phylogeny analyses of these CDPK and CRK genes demonstrate evolutionary conservation in these gene families across H. brasiliensis and other plant species. The expression of HbCPK and HbCRK genes was investigated via Solexa sequencing in a range of experimental conditions (different tissues, phases of leaf development, ethylene treatment, and various abiotic stresses). The results suggest that HbCPK and HbCRK genes are important components in growth, development, and stress responses of H. brasiliensis. Parallel studies on the CDPK and CRK gene families were also extended to five other plant species (Arabidopsis thaliana, Oryza sativa, Populus trichocarpa, Manihot esculenta, and Ricinus communis). The CDPK and CRK genes from different plant species that exhibit similar expression patterns tend to cluster together, suggesting a coevolution of gene structure and expression behavior in higher plants. The results serve as a foundation to further functional studies of these gene families in H. brasiliensis as well as in the whole plant kingdom.
ABSTRACT
Indole acetic acid (IAA) is an important regulator of adventitious rooting via the activation of complex signaling cascades. In animals, carbon monoxide (CO), mainly generated by heme oxygenases (HOs), is a significant modulator of inflammatory reactions, affecting cell proliferation and the production of growth factors. In this report, we show that treatment with the auxin transport inhibitor naphthylphthalamic acid prevented auxin-mediated induction of adventitious rooting and also decreased the activity of HO and its by-product CO content. The application of IAA, HO-1 activator/CO donor hematin, or CO aqueous solution was able to alleviate the IAA depletion-induced inhibition of adventitious root formation. Meanwhile, IAA or hematin treatment rapidly activated HO activity or HO-1 protein expression, and CO content was also enhanced. The application of the HO-1-specific inhibitor zinc protoporphyrin IX (ZnPPIX) could inhibit the above IAA and hematin responses. CO aqueous solution treatment was able to ameliorate the ZnPPIX-induced inhibition of adventitious rooting. Molecular evidence further showed that ZnPPIX mimicked the effects of naphthylphthalamic acid on the inhibition of adventitious rooting, the down-regulation of one DnaJ-like gene (CSDNAJ-1), and two calcium-dependent protein kinase genes (CSCDPK1 and CSCDPK5). Application of CO aqueous solution not only dose-dependently blocked IAA depletion-induced inhibition of adventitious rooting but also enhanced endogenous CO content and up-regulated CSDNAJ-1 and CSCDPK1/5 transcripts. Together, we provided pharmacological, physiological, and molecular evidence that auxin rapidly activates HO activity and that the product of HO action, CO, then triggers the signal transduction events that lead to the auxin responses of adventitious root formation in cucumber (Cucumis sativus).
