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Nucleotide sequence and expression of a ripening and water stress-related cDNA from tomato with homology to the MIP class of membrane channel proteins 总被引:13,自引:0,他引:13
Rupert G. Fray Andrew Wallace Donald Grierson Grantley W. Lycett 《Plant molecular biology》1994,24(3):539-543
The nucleotide sequence and derived amino acid sequence were determined for a full-length version of the tomato cDNA clone, pTOM75, the mRNA for which has previously been shown to accumulate in roots, ripening fruit and senescing leaves. Computer analysis of the predicted protein product, which we have named tomato ripening-associated membrane protein (TRAMP) indicates strong homology to known transmembrane channel proteins from other organisms. Northern analysis showed that this gene was induced by waterstress and that this induction was unaffected in an ABA-deficient genetic back-ground. 相似文献
3.
Ó Lochlainn S Bowen HC Fray RG Hammond JP King GJ White PJ Graham NS Broadley MR 《PloS one》2011,6(3):e17814
Zinc (Zn) and cadmium (Cd) hyperaccumulation may have evolved twice in the Brassicaceae, in Arabidopsis halleri and in the Noccaea genus. Tandem gene duplication and deregulated expression of the Zn transporter, HMA4, has previously been linked to Zn/Cd hyperaccumulation in A. halleri. Here, we tested the hypothesis that tandem duplication and deregulation of HMA4 expression also occurs in Noccaea.A Noccaea caerulescens genomic library was generated, containing 36,864 fosmid pCC1FOS™ clones with insert sizes ∼20–40 kbp, and screened with a PCR-generated HMA4 genomic probe. Gene copy number within the genome was estimated through DNA fingerprinting and pooled fosmid pyrosequencing. Gene copy numbers within individual clones was determined by PCR analyses with novel locus specific primers. Entire fosmids were then sequenced individually and reads equivalent to 20-fold coverage were assembled to generate complete whole contigs.Four tandem HMA4 repeats were identified in a contiguous sequence of 101,480 bp based on sequence overlap identities. These were flanked by regions syntenous with up and downstream regions of AtHMA4 in Arabidopsis thaliana. Promoter-reporter β-glucuronidase (GUS) fusion analysis of a NcHMA4 in A. thaliana revealed deregulated expression in roots and shoots, analogous to AhHMA4 promoters, but distinct from AtHMA4 expression which localised to the root vascular tissue.This remarkable consistency in tandem duplication and deregulated expression of metal transport genes between N. caerulescens and A. halleri, which last shared a common ancestor >40 mya, provides intriguing evidence that parallel evolutionary pathways may underlie Zn/Cd hyperaccumulation in Brassicaceae. 相似文献
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We report the integration of a type II restriction-methylase, mFokI, into the tobacco chloroplast genome and we demonstrate that the introduced enzyme effectively directs the methylation of its target sequence in vivo and does not affect maternal inheritance. We further report the transformation of tobacco with an E. coli dcm methylase targeted to plastids and we demonstrate efficient cytosine methylation of the plastid genome. Both adenosine methylation of FokI sites and cytosine methylation of dcm sites appeared phenotypically neutral. The ability to tolerate such plastid genome methylation is a pre-requisite for a proposed plant transgene containment system. In such a system, a chloroplast located, maternally inherited restriction methylase would provide protection from a nuclear-encoded, plastid targeted restriction endonuclease. As plastids are not paternally inherited in most crop species, pollen from such plants would carry the endonuclease transgene but not the corresponding methylase; the consequence of this should be containment of all nuclear transgenes, as pollination will only be viable in crosses to the appropriate transplastomic maternal background. 相似文献
6.
Tomatoes (Lycopersicon esculentum Mill cv. Ailsa Craig) were transformed with a gene construct having 244 bp of the 5 end of a polygalacturonase (PG) cDNA, coding for a 71 amino acid N-terminal extension to the mature protein, fused to 1320 bp of a pectinesterase (PE) cDNA encoding the full sequence of the mature PE protein. This chimaeric gene was inserted in a sense orientation between a CaMV 35S promoter and terminator for constitutive expression. In transformed tomato plants expression of the endogenous PG and PE genes in the fruit was inhibited; there was little or no observable PG and PE mRNA and a substantial reduction in the level of PG and PE enzyme activity. The transgene was expressed in the leaves of the transformed plants as demonstrated by the accumulation of mRNA, but no protein product could be identified. However, no transgene mRNA or protein were observed in the transgenic fruit.This paper represents the first report of the down-regulation of two non-homologous endogenous genes using a single gene construct. A sense gene construct was responsible for these effects. These findings are discussed in relation to possible mechanisms of action of co-suppression. 相似文献
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Xiaojuan Sun Hui He Zhihui Xie Weiping Qian Haiyen E. Zhau Leland W. K. Chung Fray F. Marshall Ruoxiang Wang 《In vitro cellular & developmental biology. Animal》2010,46(6):538-546
Prostate stromal cells may play binary roles in the process of prostate cancer development. As the first to be encountered
by infiltrating prostate cancer cells, prostate stromal cells form the first defense line against prostate cancer progression
and metastasis. However, interaction between prostate cancer and stromal cells may facilitate the formation of a tumor microenvironment
favoring cancer cell growth and survival. To establish an experimental system for studying the interaction between cancer
and stromal cells, we isolated three matched pairs of normal and cancer-associated human prostate stromal clones. In this
report, we describe the morphologic and behavioral characteristics of these cells and their effect on LNCaP prostate cancer
cells in co-culture. Unlike LNCaP prostate cancer cells, the isolated prostate stromal clones are large fibroblast-like cells
with a slow proliferation rate. Growth and survival of these clones are not affected by androgens. The stromal cells display
high resistance to serum starvation, while cancer-associated stromal clones have differentiated survival ability. In co-culture
experiments, the stromal cells protected some LNCaP prostate cancer cells from death by serum starvation, and cancer-associated
stromal clones showed more protection. This work thus established a panel of valuable human prostate stromal cell lines, which
could be used in co-culture to study the interaction between prostate cancer and prostate stromal cells. 相似文献
9.
Nuclear gene trees and the phylogenetic relationships of the mangabeys (Primates: Papionini) 总被引:2,自引:1,他引:2
Phylogenetic relationships of mangabeys within the Old World monkey tribe
Papionini are inferred from analyses of nuclear DNA sequences from five
unlinked loci. The following conclusions are strongly supported, based on
congruence among trees derived for the five separate gene regions: (1)
mangabeys are polyphyletic within the Papionini; (2) Cercocebus is the
sister taxon to the genus Mandrillus; and (3) Lophocebus belongs to a clade
with Papio and Theropithecus, with Papio as its most likely sister taxon.
Morphologically based phylogenies positing mangabey monophyly were
evaluated by mapping the sequences for each locus on these trees. The data
seem to fit these trees poorly in both maximum-parsimony and likelihood
analyses. Incongruence among nuclear gene trees occurred in the
interrelationships among Lophocebus, Papio, and Theropithecus. Several
factors that may account for this incongruence are discussed, including
sampling error, random lineage sorting, and introgression.
相似文献
10.