scholarly journals Temporal and Spatial Expression of Arabidopsis Gene Homologs Control Daylength Adaptation and Bulb Formation in Onion (Allium cepa L.)

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Md. Harun Ar Rashid ◽  
Wei Cheng ◽  
Brian Thomas

Abstract Genetic studies aimed at onion improvement have been limited because of high heterozygosity, a very large genome size with a high level of repetitive DNA and a biennial life cycle. Onion bulb initiation is daylength-dependent, which places a significant barrier to adapting new varieties for growth at different latitudes. Compared to the photoperiodic regulation of flowering, relatively little is known about genetic regulation of the bulbing process. This study aims to identify the role of gene sequences involved in daylength-regulated bulb formation and tissue specific expression of onion. A comprehensive set of developmental and spatial quantitative mRNA expression experiments were carried out to investigate expression of onion FLOWERING LOCUS T (AcFT), LEAFY (AcLFY) and GIBBERELLIN-3 OXIDASE (GA3ox1) during the bulbing response. Bulbing ratios were used to measure the response of onion plants under long day (LD) and short day (SD) conditions. AcFT1 was expressed in LD, which induces bulb formation, while AcFT4 was expressed in SD, which inhibits bulb formation. AcFT5 and AcFT6 were expressed in LD and might also be involved in bulb formation itself. All AcFT, AcLFY and GA3ox1 genes showed distinctive patterns of tissue specific expression in onion, with AcFT genes found primarily in the sites of perception in the leaf and LFY in the basal tissues, the site of response. The results are consistent with AcFT1 expression being the signal for LD-induced bulb initiation and AcFT4, being involved in suppressing bulbing in SD.

Gene ◽  
1995 ◽  
Vol 165 (2) ◽  
pp. 291-296 ◽  
Author(s):  
Marie-Annick Persuy ◽  
Sophie Legrain ◽  
Christiane Printz ◽  
Marie-Georges Stinnakre ◽  
Laurence Lepourry ◽  
...  

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3623
Author(s):  
Muhammad Y. Ali ◽  
Ana Pavasovic ◽  
Lalith K. Dammannagoda ◽  
Peter B. Mather ◽  
Peter J. Prentis

Systemic acid-base balance and osmotic/ionic regulation in decapod crustaceans are in part maintained by a set of transport-related enzymes such as carbonic anhydrase (CA), Na+/K+-ATPase (NKA), H+-ATPase (HAT), Na+/K+/2Cl−cotransporter (NKCC), Na+/Cl−/HCO${}_{3}^{-}$ cotransporter (NBC), Na+/H+exchanger (NHE), Arginine kinase (AK), Sarcoplasmic Ca+2-ATPase (SERCA) and Calreticulin (CRT). We carried out a comparative molecular analysis of these genes in three commercially important yet eco-physiologically distinct freshwater crayfish, Cherax quadricarinatus, C. destructorandC. cainii, with the aim to identify mutations in these genes and determine if observed patterns of mutations were consistent with the action of natural selection. We also conducted a tissue-specific expression analysis of these genes across seven different organs, including gills, hepatopancreas, heart, kidney, liver, nerve and testes using NGS transcriptome data. The molecular analysis of the candidate genes revealed a high level of sequence conservation across the threeCherax sp.Hyphy analysis revealed that all candidate genes showed patterns of molecular variation consistent with neutral evolution. The tissue-specific expression analysis showed that 46% of candidate genes were expressed in all tissue types examined, while approximately 10% of candidate genes were only expressed in a single tissue type. The largest number of genes was observed in nerve (84%) and gills (78%) and the lowest in testes (66%). The tissue-specific expression analysis also revealed that most of the master genes regulating pH and osmoregulation (CA, NKA, HAT, NKCC, NBC, NHE) were expressed in all tissue types indicating an important physiological role for these genes outside of osmoregulation in other tissue types. The high level of sequence conservation observed in the candidate genes may be explained by the important role of these genes as well as potentially having a number of other basic physiological functions in different tissue types.


1996 ◽  
Vol 7 (2) ◽  
pp. 183-195 ◽  
Author(s):  
Sheila Connelly ◽  
Joann M. Gardner ◽  
Alan McClelland ◽  
Michael Kaleko

1991 ◽  
Vol 11 (4) ◽  
pp. 2066-2074 ◽  
Author(s):  
J L Slack ◽  
D J Liska ◽  
P Bornstein

Studies in vitro have not adequately resolved the role of intronic and upstream elements in regulating expression of the alpha 1(I) collagen gene. To address this issue, we generated 12 separate lines of transgenic mice with alpha 1(I) collagen-human growth hormone (hGH) constructs containing different amounts of 5'-flanking sequence, with or without most of the first intron. Transgenes driven by 2.3 kb of alpha 1(I) 5'-flanking sequence, whether or not they contained the first intron, were expressed at a high level and in a tissue-specific manner in seven out of seven independent lines of transgenic mice. In most tissues, the transgene was expressed at levels approaching that of the endogenous alpha 1(I) gene and was regulated identically with the endogenous gene as animals aged. However, in lung, expression of the transgene was anomalously high, and in muscle, expression was lower than that of the endogenous gene, suggesting that in these tissues other regions of the gene may participate in directing appropriate expression. Five lines of mice were generated containing transgenes driven by 0.44 kb of alpha 1(I) 5'-flanking sequence (with or without the first intron), and expression was detected in four out of five of these lines. The level of expression of the 0.44-kb constructs in the major collagen-producing tissues was 15- to 500-fold lower than that observed with the longer 2.3-kb promoter. While transgenes containing the 0.44-kb promoter and the first intron retained a modest degree of tissue-specific expression, those without the first intron lacked tissue specificity and were poorly expressed in all tissues except lung.(ABSTRACT TRUNCATED AT 250 WORDS)


1991 ◽  
Vol 11 (4) ◽  
pp. 2066-2074
Author(s):  
J L Slack ◽  
D J Liska ◽  
P Bornstein

Studies in vitro have not adequately resolved the role of intronic and upstream elements in regulating expression of the alpha 1(I) collagen gene. To address this issue, we generated 12 separate lines of transgenic mice with alpha 1(I) collagen-human growth hormone (hGH) constructs containing different amounts of 5'-flanking sequence, with or without most of the first intron. Transgenes driven by 2.3 kb of alpha 1(I) 5'-flanking sequence, whether or not they contained the first intron, were expressed at a high level and in a tissue-specific manner in seven out of seven independent lines of transgenic mice. In most tissues, the transgene was expressed at levels approaching that of the endogenous alpha 1(I) gene and was regulated identically with the endogenous gene as animals aged. However, in lung, expression of the transgene was anomalously high, and in muscle, expression was lower than that of the endogenous gene, suggesting that in these tissues other regions of the gene may participate in directing appropriate expression. Five lines of mice were generated containing transgenes driven by 0.44 kb of alpha 1(I) 5'-flanking sequence (with or without the first intron), and expression was detected in four out of five of these lines. The level of expression of the 0.44-kb constructs in the major collagen-producing tissues was 15- to 500-fold lower than that observed with the longer 2.3-kb promoter. While transgenes containing the 0.44-kb promoter and the first intron retained a modest degree of tissue-specific expression, those without the first intron lacked tissue specificity and were poorly expressed in all tissues except lung.(ABSTRACT TRUNCATED AT 250 WORDS)


2013 ◽  
Author(s):  
AL Bookout ◽  
Y Jeong ◽  
M Downes ◽  
RT Yu ◽  
RM Evans ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document