Characterization of Aldehyde Oxidase (AO) Genes Involved in the Accumulation of Carotenoid Pigments in Wheat Grain

Abstract

Aldehyde Oxidase (AO) enzyme (EC 1.2.3.1) catalyzes the final steps of carotenoid catabolism and it is a key enzyme in the abscisic acid (ABA) biosynthesis. AO isoforms are located in the cytosolic compartment of tissues in many plants, where induce the oxidation of aldehydes into carboxylic acid, and in addition, catalyze the hydroxylation of some heterocycles. The goal of the present study was to characterize the AO genes involved in the accumulation of carotenoid pigments in wheat grain, an important quantitative trait controlled by multiple genes. The cDNAs corresponding to the four AO isoforms from Arabidopsis thaliana and five AO isoforms from Brachypodium distachyon were used as query in 454 sequence assemblies data for Triticum aestivum cv. Chinese Spring (https://urgi.versailles.inra.fr/blast/blast.php) to obtain the partial or whole orthologous wheat AO sequences. Three wheat isoforms, designated AO1, AO2, and AO3 were located on the chromosome groups 2, 5, and 7, respectively, and mapped on two consensus wheat maps by SNP markers located within the AO gene sequences. To validate the possible relationships between AO3 genes and carotenoid accumulation in wheat, the expression levels of AO-A3 and AO-B3 gene were determined during the kernel maturation stage of two durum wheat cultivars, Ciccio and Svevo, characterized by a low and high carotenoid content, respectively. Different AO-A3 gene expression values were observed between the two cultivars indicating that the AO-A3 allele present in Ciccio was more active in carotenoid degradation. A gene marker was developed and can be used for marker-assisted selection in wheat breeding programs.

Participation of Wheat and Rye Genome in Drought Induced Senescence in Winter Triticale (X Triticosecale Wittm.)

“…Plant senescence is a process controlled by multiple genes [51]. Some of them encode enzymes responsible for protein degradation [1], protein processing [52], N mobilization [53], lipid degradation [54], C mobilization [1], cell wall degradation [55], P mobilization [56], transport [57], transcriptional regulation [58], signaling pathways [59], antioxidants [7], metal binding [60], hormone biosynthesis [61], cell death [62], defense-related genes [52], translation [63] and some proteins of unknown functions [64]. These proteins involve also those related to carbohydrate metabolism, such as isocitrate lyase, malate synthase, pyruvate orthophosphate dikinase, sugar transporter, endoxyloglucan transferase or β glucosidase [51,65].…”

“…In many species, the first visible sign of senescence is yellowing of leaves due to chlorophyll degradation and the appearance of other dominant pigments, mainly carotenoids, xanthophylls and anthocyanins [7]. Possessing the stay green-trait closely correlates with delayed plant senescence, which is why leaf greenness index or green leaf area constitute reliable indicators of the process [8].…”

The content of yellow pigments in durum wheat (Titicum durum Desf.) grains: biosynthesis, genetic control, marker selection

“…В частности, в длинном плече хромосомы 7A были идентифицированы два QTL с противоположными эффектами. Локус с негативным эффектом по отношению к признакам YPC и YI был ассоциирован с аллельными вариациями гена альдегидоксидазы (АО) -фермента, катализирующего деградацию каротиноидов в результате их окисления (Colasuonno et al, 2014(Colasuonno et al, , 2017b. Второй (QTL-73), расположенный в области локализации гена Psy-1, оказывал положительный эффект (до 60 % вариации) на признак YPC.…”

“…Количественные различия генотипов по на-СЕЛЕКЦИЯ РАСТЕНИЙ / PLANT BREEDING коплению пигментов связаны с аллельным разнообразием генов PSY -фитоенсинтетазы (Pozniak et al, 2007;He et al, 2008;Dibari et al, 2012;Colasuonno et al, 2014;Campos et al, 2016), LCYE -ликопин-ε-циклазы (Howitt et al, 2009;Crawford, Francki, 2013), LCYB -ликопин-βциклазы (Zeng et al, 2015), HYD -β-гидроксилазы (Qin et al, 2012), PDS (фитоендесатуразы) и ZDS -каротиндесатуразы (Cong et al, 2010). Катаболические гены контролируют активность альдегидоксидазы -АО (Colasuonno et al, 2017b), полифенолоксидазы -РРО (Watanabe et al, 2004(Watanabe et al, , 2006Si et al, 2012), липоксигеназы -LOX или Lpx (DeSimone еt al., 2010; Randhawa et al, 2013) и пероксидазы -PER (Ficco et al, 2014), снижающих концентрацию пигментов и потребительские качества конечных продуктов. Наиболее значимые гены, их аллельные варианты и маркеры обсуждаются в тексте и представлены в табл.…”

“…Значительное влияние на признаки YI, YPC и цвет макаронных изделий оказывает альдегидоксидаза (АО; ЕС 1.2.3.1) (Colasuonno et al, 2017b). Три изоформы фермента пшеницы, АО1, АО2, АО3, были локализованы на 2-, 5-, 7-хромосомных группах соответственно.…”