Table 1. HCOGs with conserved cold responses in all five Pooideae species.
These 16 genes had the same type of cold response (short or long term) with the same manner of expression change (up- or down-regulation) in all five species. L, Responsive to long-term cold treatment; S, responsive to short-term cold treatment; ↗, up-regulated; ↘, down-regulated. Annotations were inferred from the literature using orthologs.
| B. distachyon Ortholog | Description and Relation to Stress Response | Response |
|---|---|---|
| Bradi2g39230 | Hyperosmolality-gated CA2+-permeable channel (OSCA). Stress-activated calcium channels (Yuan et al., 2014) that are highly conserved in eukaryotes (Hou et al., 2014); in O. sativa, OSCA genes are differentially expressed in response to osmotic stress (Li et al., 2015) | S↗ |
| Bradi2g06830 | Calcium-binding EF hand-containing calcium exchange channel (EF-CAX). Calcium ions are important mediators of abiotic stress in plants (Day et al., 2002; Bose et al., 2011); expression of calcium-binding proteins correlates with exposure to cold stress in several plants, such as Arabidopsis (Thomashow, 1999), Musa × paradisiaca (Yang et al., 2015), and H. vulgare (Greenup et al., 2011) | S↗ |
| Bradi2g05226 | GIGANTEA. Promotes flower development in plants (Andrés and Coupland, 2012); in Arabidopsis, this gene is involved in CBF-independent freezing tolerance (Cao et al., 2005; Xie et al., 2015), and it is responsive to cold in Z. mays (Sobkowiak et al., 2014); also part of the circadian clock | S↗ |
| Bradi4g24967 | Arabidopsis Pseudo-Response Regulator3-like (AtPRR3-like). AtPRR3 is a member of the circadian clock quintet AtPRR1/TOC1 (Murakami-Kojima et al., 2002; Murakami et al., 2004); no association with stress response found in the literature; however, AtPRR3-like might be closer related to AtPRR5/9 than to AtPRR3 (see Bradi4g36077, PRR95) | S↗ |
| Bradi2g09060 | Triacylglycerol lipase, α/β-hydrolase superfamily. Studies in Arabidopsis (Wang et al., 2011) and Ipomoea batatas (Liu et al., 2009) suggest that genes with α/β-hydrolase domains respond to osmotic stress; in Triticum monococcum, atriacylglycerol lipase was induced by pathogen stress (Guan et al., 2015) | S↗ |
| Bradi2g07480 | Late-Embryogenesis-Abundant protein14 (LEA-14). Responsive to drought, salt, and cold stress in Arabidopsis (Kimura et al., 2003; Singh et al., 2005), Betula pubescens (Rinne et al., 1998), and B. distachyon (Gagné-Bourque et al., 2015) | S↗ |
| Bradi1g04150 | SNAC1-like/NAC transcription factor67. NAC transcription factors mediate abiotic stress responses; osmotic stress increases the expression of SNAC1 in O. sativa (Nakashima et al., 2012), NAC68 in M. paradisiaca (Negi et al., 2015; Yang et al., 2015), and NAC67 in T. aestivum (Mao et al., 2014) | S↗ |
| Bradi4g36077 | Pseudo-Response Regulator95 (PRR95). Homologous to conserved circadian clock gene AtPRR5/9 (Murakami et al., 2003; Campoli et al., 2012); AtPRR5 gene is cold regulated in Arabidopsis (Lee et al., 2005), and PRR95 is cold responsive in Z. mays (Sobkowiak et al., 2014) | S↗ |
| Bradi2g43040 | DnaJ chaperon protein. DnaJ cochaperons are vital in stress response and have been found to be involved in the maintenance of PSII under chilling stress and to enhance drought tolerance in tomato (Solanum lycopersicum; Kong et al., 2014; Wang et al., 2014) | S+L↗ |
| Bradi3g33080 | Glycogenin Glucuronosyltransferase (GGT). GGT belongs to the GT8 protein family (Yin et al., 2011); in O. sativa, OsGGT transcripts are induced in submerged plants and respond to various abiotic stresses except cold (Qi et al., 2005; Uddin et al., 2012) | L↗ |
| Bradi1g04500 | Major facilitator superfamily transporter. Association with stress response unknown | L↗ |
| Bradi3g14080 | Glycosyl transferase. Association with stress response unknown | L↗ |
| Bradi1g35357 | Uncharacterized membrane protein. Association with stress response unknown | S↗ |
| Bradi2g48850 | Uncharacterized protein. Association with stress response unknown | S↗ |
| Bradi1g33690 | Uncharacterized protein. Association with stress response unknown | S↗ |
| Bradi1g07120 | Putative S-adenosyl-l-Met-dependent methyltransferase. Association with stress response unknown | L↘ |