115 research outputs found
Transcriptome profiling of ripening nectarine (Prunus persica L. Batsch) fruit treated with 1-MCP
A large-scale transcriptome analysis has been conducted using mPEACH1.0 microarray on nectarine (Prunus persica L. Batsch) fruit treated with 1-methylcyclopropene (1-MCP). 1-MCP maintained flesh firmness but did not block ethylene biosynthesis. Compared with samples at harvest, only nine genes appeared to be differentially expressed when fruit were sampled immediately after treatment, while a total of 90 targets were up- or down-regulated in untreated fruit. The effect of 1-MCP was confirmed by a direct comparison of transcript profiles in treated and untreated fruit after 24 h of incubation with 106 targets differentially expressed. About 30% of these targets correspond to genes involved in primary metabolism and response processes related to ethylene, auxin, and other hormones. In treated fruit, altered transcript accumulation was detected for some genes with a role in ripening-related events such as softening, colour development, and sugar metabolism. A rapid decrease in flesh firmness and an increase in ethylene production were observed in treated fruit maintained for 48 h in air at 20 ºC after the end of the incubation period. Microarray comparison of this sample with untreated fruit 24 h after harvest revealed that about 45% of the genes affected by 1-MCP at the end of the incubation period changed their expression during the following 48 h in air. Among these genes, an ethylene receptor (ETR2) and three ethylene responsive factors (ERF) were present, together with other transcription factors and ethylene-dependent genes involved in quality parameter changes
Investigations into the molecular and physiological factors influencing low temperature breakdown in stonefruit
Cold storage is essential for the successful distribution of stonefruit to distant markets; however most cultivars suffer chilling injury (CI), commonly referred to as low temperature breakdown (LTB). LTB is a significant problem for industry and the genetic factors responsible for its onset are not understood. Treatment of stonefruit with the ethylene antagonist, 1-methylcyclopropene (1-MCP) before cold
storage has been shown to differentially affect the development of CI in peaches and plums. 1-MCP treatment increases the incidence of LTB in peaches but reduces it in plums (Fernández-Trujillo and Artés, 1997; Fan et al., 2002). These observations were confirmed and preliminary research into the effects of 1-MCP and cold storage
on gene expression is reported herein
phosphorus and potassium fertilizer effects on alfalfa and soil in a non limited soil
Fertilization strategies for high-yielding alfalfa (Medicago sativa L.) should take in account the increase in soil nutritional status that occurred during the last decades in areas with intensive agricultural use. A field study was conducted at the University of Padova, northeastern Italy, to determine the response of alfalfa yield and nutritive value to various combinations of P and K rates in a soil lacking nutrient deficiency. Alfalfa cultivar Delta was seeded in March 2005 on a silt loam soil having 38 mg kg -1 available P and 178 mg kg -1 exchangeable K. Nine treatments deriving from the combination of three P fertilization rates (0, 100, and 200 kg ha -1 P 2 O 5 ) and three K rates (0, 300, and 600 kg ha -1 K 2 O) were compared in a randomized complete block design. Plots were harvested at bud stage during three growing seasons (2005-2007) and dry matter (DM) yield, forage nutritive value, P and K contents, canopy height, and stem density were measured at each harvest. Soil samples were collected at the end of the research period for determination of available P and exchangeable K. The results demonstrated that P application had no impact on yield and did not interact with K in determining productivity, while K had a positive effect on yield. However, the 300 kg ha -1 K 2 O rate appeared sufficient to maximize yield, without adverse effects on the forage nutritive value. Data from soil analyses showed that alfalfa has a high K uptake even when it is fertilized at high rates
Bone health and body composition in transgender adults before gender-affirming hormonal therapy: data from the COMET study
Purpose: Preliminary data suggested that bone mineral density (BMD) in transgender adults before initiating gender-affirming hormone therapy (GAHT) is lower when compared to cisgender controls. In this study, we analyzed bone metabolism in a sample of transgender adults before GAHT, and its possible correlation with biochemical profile, body composition and lifestyle habits (i.e., tobacco smoke and physical activity). Methods: Medical data, smoking habits, phospho-calcic and hormonal blood tests and densitometric parameters were collected in a sample of 125 transgender adults, 78 Assigned Females At Birth (AFAB) and 47 Assigned Males At Birth (AMAB) before GAHT initiation and 146 cisgender controls (57 females and 89 males) matched by sex assigned at birth and age. 55 transgender and 46 cisgender controls also underwent a complete body composition evaluation and assessment of physical activity using the International Physical Activity Questionnaire (IPAQ). Results: 14.3% of transgender and 6.2% of cisgender sample, respectively, had z-score values < -2 (p = 0.04). We observed only lower vitamin D values in transgender sample regarding biochemical/hormonal profile. AFAB transgender people had more total fat mass, while AMAB transgender individuals had reduced total lean mass as compared to cisgender people (53.94 ± 7.74 vs 58.38 ± 6.91, p < 0.05). AFAB transgender adults were more likely to be active smokers and tend to spend more time indoor. Fat Mass Index (FMI) was correlated with lumbar and femur BMD both in transgender individuals, while no correlations were found between lean mass parameters and BMD in AMAB transgender people. Conclusions: Body composition and lifestyle factors could contribute to low BMD in transgender adults before GAHT
Hubble Space Telescope survey of Magellanic Cloud star clusters. Photometry and astrometry of 113 clusters and early results
In the past years, we have undertaken an extensive investigation of LMC and
SMC star clusters based on HST data. We present photometry and astrometry of
stars in 101 fields observed with the WFC/ACS, UVIS/WFC3 and NIR/WFC3 cameras.
These fields comprise 113 star clusters. We provide differential-reddening maps
and illustrate various scientific outcomes that arise from the early inspection
of the photometric catalogs. In particular, we provide new insights on the
extended main-sequence turn-off (eMSTO) phenomenon: i) We detected eMSTOs in
two clusters, KMHK361 and NGC265, which had no previous evidence of multiple
populations. This finding corroborates the conclusion that the eMSTO is a
widespread phenomenon among clusters younger than ~2 Gyr. ii) The homogeneous
color-magnitude diagrams (CMDs) of 19 LMC clusters reveal that the distribution
of stars along the eMSTO depends on cluster age. iii) We discovered a new
feature along the eMSTO of NGC1783, which consists of a distinct group of stars
going on the red side of the eMSTO in CMDs composed of ultraviolet filters.
Furthermore, we derived the proper motions of stars in the fields of view of
clusters with multi-epoch images. Proper motions allowed us to separate the
bulk of bright field stars from cluster members and investigate the internal
kinematics of stellar populations in various LMC and SMC fields. As an example,
we analyze the field around NGC346 to disentangle the motions of its stellar
populations, including NGC364 and BS90, young and pre-MS stars in the
star-forming region associated with NGC346, and young and old field stellar
populations of the SMC. Based on these results and the fields around five
additional clusters, we find that young SMC stars exhibit elongated
proper-motion distributions that point toward the LMC, thus bringing new
evidence for a kinematic connection between the LMC and SMC.Comment: 37 pages, 27 figures, accepted for publication in Astronomy &
Astrophysic
Expression of auxin-binding protein1 during plum fruit ontogeny supports the potential role of auxin in initiating and enhancing climacteric ripening
Auxin-binding protein1 (ABP1) is an active element involved in auxin signaling and plays critical roles in auxin-mediated plant development. Here, we report the isolation and characterization of a putative sequence from Prunus salicina L., designated PslABP1. The expected protein exhibits a similar molecular structure to that of well-characterized maize-ABP1; however, PslABP1 displays more sequence polarity in the active-binding site due to substitution of some crucial amino-acid residues predicted to be involved in auxin-binding. Further, PslABP1 expression was assessed throughout fruit ontogeny to determine its role in fruit development. Comparing the expression data with the physiological aspects that characterize fruit-development stages indicates that PslABP1 up-regulation is usually associated with the signature events that are triggered in an auxin-dependent manner such as floral induction, fruit initiation, embryogenesis, and cell division and elongation. However, the diversity in PslABP1 expression profile during the ripening process of early and late plum cultivars seems to be due to the variability of endogenous auxin levels among the two cultivars, which consequently can change the levels of autocatalytic ethylene available for the fruit to co-ordinate ripening. The effect of auxin on stimulating ethylene production and in regulating PslABP1 was investigated. Our data suggest that auxin is involved in the transition of the mature green fruit into the ripening phase and in enhancing the ripening process in both auxin- and ethylene-dependent manners thereafter
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