Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.3.16 (
calcineurin
)
17,112
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
While the phytotoxic responses of arsenic (As) on plants have been studied extensively, based on physiological and biochemical aspects, very little is known about As stress-elicited changes in plants at the proteome level. Hydroponically grown 2-wk-old rice seedlings were exposed to different doses of arsenate, and roots were collected after 4 days of treatment, as well as after a recovery period. To gain a comprehensive understanding of the precise mechanisms underlying As toxicity, metabolism, and the defense reactions in plants, a comparative proteomic analysis of rice roots has been conducted in combination with physiological and biochemical analyses. Arsenic treatment resulted in increases of As accumulation, lipid peroxidation, and in vivo H(2)O(2) contents in roots. A total of 23 As-regulated proteins including predicted and novel ones were identified using 2-DE coupled with MS analyses. The expression levels of
S-adenosylmethionine synthetase
(
SAMS
), GSTs, cysteine synthase (CS), GST-tau, and tyrosine-specific
protein phosphatase
proteins (TSPP) were markedly up-regulated in response to arsenate, whereas treatment by H(2)O(2) also regulated the levels of CS suggesting that its expression was certainly regulated by As or As-induced oxidative stress. In addition, an omega domain containing GST was induced only by arsenate. However, it was not altered by treatment of arsenite, copper, or aluminum, suggesting that it may play a particular role in arsenate stress. Analysis of the total glutathione (GSH) content and enzymatic activity of glutathione reductase (GR) in rice roots during As stress revealed that their activities respond in a dose-dependent manner of As. These results suggest that
SAMS
, CS, GSTs, and GR presumably work synchronously wherein GSH plays a central role in protecting cells against As stress.
...
PMID:Comparative proteomic study of arsenic-induced differentially expressed proteins in rice roots reveals glutathione plays a central role during As stress. 1875 4
To further our understanding of one-carbon metabolism in the protozoan parasite
Leishmania
, we conducted genomic screens to study how the parasite responded to sinefungin (SNF) selection. SNF is a structural analogue of
S
-adenosylmethionine (AdoMet), a key methyl group donor to a number of biomolecules. One screen consisted of sequencing SNF-resistant mutants generated by stepwise selection with gradually increasing drug concentrations. These studies demonstrated deletion of the AdoMet transporter (AdoMetT1) by intergenic recombination as a crucial loss-of-function marker for SNF resistance. The second screen consisted of Cos-seq, a gain-of-function cosmid-based genomewide functional screen with increasing SNF concentration coupled to next-generation sequencing. Cosmids enriched in that screen and sequenced led to the identification of (i) the
AdoMet synthetase
(METK) as the major SNF target, (ii) an mRNA [(guanine-N7)-methyltransferase (CMT1)], (iii) a leucine carboxyl methyltransferase (LCMT), (iv) two tryparedoxin genes, and (v) two
protein phosphatase
regulatory genes. Further functional exploration indicated that LCMT interacts with one phosphatase catalytic subunit (PP2AC) and that mutation of the C-terminal leucine residue of PP2AC affects sinefungin susceptibility. These holistic screens led to the identification of transporters, biosynthetic genes, RNA and protein methyltransferases, as well as phosphatases linked to AdoMet-mediated functions in
Leishmania
IMPORTANCE
The two main cellular metabolic one-carbon donors are reduced folates and
S
-adenosylmethionine, whose biosynthetic pathways have proven highly effective in chemotherapeutic interventions in various cell types. Sinefungin, a nucleoside analogue of
S
-adenosylmethionine, was shown to have potent activity against the protozoan parasite
Leishmania
Here, we studied resistance to sinefungin using whole-genome approaches as a way to further our understanding of the role of
S
-adenosylmethionine in this parasite and to reveal novel potential drug targets. These approaches allowed the characterization of novel features related to
S
-adenosylmethionine function in
Leishmania
which could further help in the development of sinefungin-like compounds against this pathogenic parasite.
...
PMID:Genomewide Analysis of Mode of Action of the
S
-Adenosylmethionine Analogue Sinefungin in Leishmania infantum. 3161 76