In order to elaborate on the origin of the core Eudicot Class II SDHs, plant genomes containing SDHs from both Class I and Class II were selected.
"sdh-pep.fas" contains amino acid sequences for the plant SDH sub-branch.
Enriched GO parent terms such as "response to stimulus" and descendent terms "response to abiotic stimulus", were frequently enriched in SDH Class I co-expressed lists and slightly in SDH Class II containing plant species.
SDH assay: Two cuvettes containing 950 µl SDH buffer (50 mM Tris-H2SO4 pH 7.4, 0.1 mM EDTA, 1 mM KCN, 0.1% Triton X-100), 0.25% succinate, 70 µM dichlorophenol-indophenol, and 60 µM decylubiquinone were prepared.
For collinear SDH gene pair identification, amino acid sequences and genetic position information of chromosomes containing SDHs were extracted from each species, then combined to perform the multi-species MCScanX analysis.
OCT activity was ascertained by adding 1 mM succinyl-CoA, 1 mM oxalate, 15 µg of protein equivalent from P.fluorescens membrane fraction (which contains SDH), INT, PMS, and reaction buffer.
The 5' portion of the sequence encodes the LKR activity of the bifunctional enzyme, which is encoded by eleven exons (blue boxes in Figure 1B); the 3' part of the sequence encodes for SDH activity and contains twelve exons (red boxes).
To investigate the function of LKR/SDH in ticks we constructed small dsRNAs containing LKR or SDH domains and used them for RNA silencing experiments.
It is known that Tcm62 forms a complex containing at least three SDH subunits Sdh1, Sdh2 and Sdh3 [ 29], and all these SDH genes are involved in aerobic respiration [ 30], which is consistent with the function of HAP4 and its target genes.
Recent studies have revealed that potato [ 53], citrus fruits [ 63] and pear [ 64, 65] (all containing Class II SDHs) also produce TA, although to a lesser degree than V. vinifera.
In a recent gene-expression study by Dahia et al. of sporadic, SDHB-, SDHD -, VHL-, MEN2- and NF1-associated phaeochromocytomas, two phaeochromocytoma clusters were identified: a cluster containing VHL-, and SDH- linked tumors and another containing MEN2- and NF1-linked tumors[ 9].
