Summary 2,4-dichlorophenoxyacetic acid (2,4-D), a chemical analogue of indole-3-acetic acid (IAA), is widely used as a growth regulator and exogenous source of auxin. Because 2,4-D evokes physiological and molecular responses similar to those evoked by IAA, it is believed that they share a common response pathway. Here, we show that a mutant, antiauxin resistant1 (aar1), identified in a screen for resistance to the anti-auxin p-chlorophenoxyisobutyric acid (PCIB), is resistant to 2,4-D, yet nevertheless responds like the wild-type to IAA and 1-napthaleneacetic acid in root elongation and lateral root induction assays. That the aar1 mutation alters 2,4-D responsiveness specifically was confirmed by analysis of GUS expression in the DR5:GUS and HS:AXR3NT-GUS backgrounds, as well as by real-time PCR quantification of IAA11 expression. The two characterized aar1 alleles both harbor multi-gene deletions; however, 2,4-D responsiveness was restored by transformation with one of the genes missing in both alleles, and the 2,4-D-resistant phenotype was reproduced by decreasing the expression of the same gene in the wild-type using an RNAi construct. The gene encodes a small, acidic protein (SMAP1) with unknown function and present in plants, animals and invertebrates but not in fungi or prokaryotes. Taken together, these results suggest that SMAP1 is a regulatory component that mediates responses to 2,4-D, and that responses to 2,4-D and IAA are partially distinct.
A mutant showing a long coleoptile phenotype under white light was isolated from gamma-ray-mutagenized rice (cv. Nihonmasari). This mutant, named cpm1 (coleoptile photomorphogenesis 1), has been found to be impaired in phytochrome-mediated inhibition of coleoptile growth. Another outstanding feature of the mutant is impaired anthesis. Under red light (R), cpm1 coleoptiles elongate at a higher rate than wild-type (WT) coleoptiles, owing to substantially reduced responsiveness to R. This phenotype occurs in an age-dependent manner, and cpm1 coleoptiles become responsive to R as they elongate. The impairment was found in both very-low-fluence and low-fluence responses. Mutant coleoptiles also elongate longer than WT coleoptiles in darkness, but in this case the long coleoptile results from an extended elongation period. The cpm1 mutation does not affect the following phytochrome responses: the growth stimulation in submerged coleoptiles (uncovered in this study), potentiation of greening, and down-regulation of PHYA transcription. The cpm1 mutation does not significantly affect the level of spectroscopically detectable phytochrome and the transcription levels of three phytochrome genes (PHYA-C). It is concluded that the CPM1 gene is involved in the phytochrome signal transduction that specifically leads to growth inhibition. Some aspects of rice seedling photomorphogenesis are discussed in relation to the results obtained.
To isolate novel auxin-responsive mutants in Arabidopsis (Arabidopsis thaliana), we screened mutants for root growth resistance to a putative antiauxin, p-chlorophenoxyisobutyric acid (PCIB), which inhibits auxin action by interfering the upstream auxinsignaling events. Eleven PCIB-resistant mutants were obtained. Genetic mapping indicates that the mutations are located in at least five independent loci, including two known auxin-related loci, TRANSPORT INHIBITOR RESPONSE1 and Arabidopsis CULLIN1. antiauxin-resistant mutants (aars) aar3-1, aar4, and aar5 were also resistant to 2,4-dichlorophenoxyacetic acid as shown by a root growth assay. Positional cloning of aar3-1 revealed that the AAR3 gene encodes a protein with a domain of unknown function (DUF298), which has not previously been implicated in auxin signaling. The protein has a putative nuclear localization signal and shares homology with the DEFECTIVE IN CULLIN NEDDYLATION-1 protein through the DUF298 domain. The results also indicate that PCIB can facilitate the identification of factors involved in auxin or auxin-related signaling.
BackgroundAdoption of modern contraceptive methods after menstrual regulation (MR) is thought to reduce subsequent unwanted pregnancy and abortion. Long-acting reversible contraceptives (LARCs) are highly effective at reducing unintended pregnancy, but uptake in Bangladesh is low. Providing information on the most effective methods of contraception increases uptake of more effective methods. This protocol describes a randomised controlled trial of an intervention delivered by mobile phone designed to support post-MR contraceptive use in Bangladesh.MethodsThis is a multi-site single blind individual randomised controlled trial. At least 960 women undergoing MR procedures at selected facilities will be recruited after their procedure by female research assistants. Women will be randomised into the control or intervention group with a 1:1 ratio.All participants will receive usual clinic care, including contraceptive counselling and the telephone number of a non-toll-free call centre which provides counselling on MR and contraception. During the 4 months after their MR procedure, intervention participants will be sent 11 recorded interactive voice messages to their mobile phone about contraception with a focus on their chosen method and LARCs. Each message allows the participant to connect directly to the call centre. The intervention is free to the user. The control group will receive no messages delivered by mobile phone. All participants will be asked to complete an in-person questionnaire at recruitment and follow-up questionnaires by telephone at 2 weeks, 4 months and 12 months after their MR. The primary outcome for the trial will be self-reported LARC use 4 months post-MR. Secondary outcomes include LARC use at 2 weeks and 12 months post-MR, use of any effective modern contraceptive method at 2 weeks, 4 months and 12 months post-MR, and contraceptive discontinuation, contraceptive method switching, pregnancy, subsequent MR and experience of violence during the 12 month study period.DiscussionMobile phones offer a low-cost mechanism for providing individualised support to women with contraception outside of the clinic setting. This study will provide information on the effects of such an intervention among MR clients in Bangladesh.Trial registrationTrial registered with clinicaltrials.gov Registration number: NCT02579785 Date of registration: 16th October 2015.
Little is known about barriers to MR services, and whether women denied MR seek abortion elsewhere, self-induce, or continue the pregnancy. Methods: After obtaining authorization from four health facilities in Bangladesh, we recruited eligible and interested women in to the study and requested informed consent for study participation. We conducted in-depth interviews with 20 women denied MR from four facilities in four districts in Bangladesh. Interviews were translated and transcribed, and the transcripts were analyzed by two researchers through an iterative process using a qualitative content analysis approach. Results: Of those interviewed, 12 women sought abortion elsewhere and eight of these women were successful; four women who sought subsequent services were denied again. Two of the eight women who subsequently terminated their pregnancies suffered from complications. None of the participants were aware of the legal gestational limit for government-approved MR services. Given that all participants were initially denied services because they were beyond the legal gestational limit for MR and there were no reported risks to any of the mothers' health, we presume that the eight terminations performed subsequently were done illegally. Conclusions: Barriers to seeking safe MR services need to be addressed to reduce utilization of potentially unsafe alternative abortion services and to improve women's health and well being in Bangladesh. Findings from this study indicate a need to raise awareness about legal MR services; provide information to women on where, how and when they can access these services; train more MR providers; improve the quality and safety of second trimester services; and strengthen campaigns to educate women about contraception and pregnancy risk throughout the reproductive lifespan to prevent unintended pregnancies.
The terpenoids, or isoprenoids, are a large family of natural products that are best known as constituents of the essential oils in plants. Because of their pleasant flavor and aromatic properties, essential oils have an economic importance in perfumery, cosmetic, pharmaceutical and various other industries. However, expression profiles of regulatory genes in essential oil production have not been dissected entirely, which may be an interesting topic of future research. In this report, we review recent studies on isoprenoids biosynthesis in plants. We also discuss the progress of our recent research activities on isoprenoid studies.
BackgroundAs access to mobile technology improves in low- and middle-income countries, it becomes easier to provide information about sensitive issues, such as contraception and abortion. In Bangladesh, 97% of the population has access to a mobile signal, and the equity gap is closing in mobile phone ownership. Bangladesh has a high pregnancy termination rate and improving effective use of contraception after abortion is essential to reducing subsequent unwanted pregnancies.ObjectiveThis study examines the feasibility and acceptability of implementing a short message service (SMS) text message-based mHealth intervention to support postabortion contraceptive use among abortion clients in Bangladesh, including women’s interest in the intervention, intervention preferences, and privacy concerns.MethodsThis feasibility study was conducted in four urban, high abortion caseload facilities. Women enrolled in the study were randomized into an intervention (n=60) or control group (n=60) using block randomization. Women completed a baseline interview on the day of their abortion procedure and a follow-up interview 4 months later (retention rate: 89.1%, 107/120). Women in the intervention group received text message reminders to use their selected postabortion contraceptive methods and reminders to contact the facility if they had problems or concerns with their method. Women who did not select a method received weekly messages that they could visit the clinic if they would like to start a method. Women in the control group did not receive any messages.ResultsAlmost all women in the feasibility study reported using their mobile phones at least once per day (98.3%, 118/120) and 77.5% (93/120) used their phones for text messaging. In the intervention group, 87% (48/55) of women were using modern contraception at the 4-month follow-up, whereas 90% (47/52) were using contraception in the control group (P=.61). The intervention was not effective in increasing modern contraceptive use at follow-up, but 93% (51/55) of women reported at follow-up that the text reminders helped them use their method correctly and 76% (42/55) said they would sign up for this service again. Approximately half of the participants (53%, 29/55) said that someone they did not want to know about the text message reminders found out, mostly their husbands or children.ConclusionsIn this small-scale feasibility study, text reminders did not increase postabortion contraceptive use. Despite the ineffectiveness of the text reminder intervention, implementation of a mHealth intervention among abortion clients in urban Bangladesh was feasible in that women were interested in receiving follow-up messages after their abortion and mobile phone use was common. Text messages may not be the best modality for a mHealth intervention due to relatively low baseline SMS text message use and privacy concerns.
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