Components of the Arabidopsis C-Repeat/Dehydration-Responsive Element Binding Factor Cold-Response Pathway Are Conserved inBrassica napus and Other Plant Species

Abstract

Many plants increase in freezing tolerance in response to low, nonfreezing temperatures, a phenomenon known as cold acclimation. Cold acclimation in Arabidopsis involves rapid cold-induced expression of the C-repeat/dehydrationresponsive element binding factor (CBF) transcriptional activators followed by expression of CBF-targeted genes that increase freezing tolerance. Here, we present evidence for a CBF cold-response pathway in Brassica napus. We show that B. napus encodes CBF-like genes and that transcripts for these genes accumulate rapidly in response to low temperature followed closely by expression of the cold-regulated Bn115 gene, an ortholog of the Arabidopsis CBF-targeted COR15a gene. Moreover, we show that constitutive overexpression of the Arabidopsis CBF genes in transgenic B. napus plants induces expression of orthologs of Arabidopsis CBF-targeted genes and increases the freezing tolerance of both nonacclimated and cold-acclimated plants. Transcripts encoding CBF-like proteins were also found to accumulate rapidly in response to low temperature in wheat (Triticum aestivum L. cv Norstar) and rye (Secale cereale L. cv Puma), which cold acclimate, as well as in tomato (Lycopersicon esculentum var. Bonny Best, Castle Mart, Micro-Tom, and D Huang), a freezing-sensitive plant that does not cold acclimate. An alignment of the CBF proteins from Arabidopsis, B. napus, wheat, rye, and tomato revealed the presence of conserved amino acid sequences, PKK/RPAGRxKFxETRHP and DSAWR, that bracket the AP2/EREBP DNA binding domains of the proteins and distinguish them from other members of the AP2/EREBP protein family. We conclude that components of the CBF cold-response pathway are highly conserved in flowering plants and not limited to those that cold acclimate.Plants vary greatly in their abilities to survive freezing temperatures (Sakai and Larcher, 1987). Whereas plants from tropical regions have essentially no capacity to withstand freezing, herbaceous plants from temperate regions can survive freezing at temperatures ranging from Ϫ5 to Ϫ30°C, depending on the species. It is significant that the maximum freezing tolerance of plants is not constitutive, but is induced in response to low temperatures (below approximately 10°C), a phenomenon known as "cold acclimation" (Hughes and Dunn, 1996;Thomashow, 1999). Nonacclimated wheat (Triticum aestivum L. cv Norstar) plants, for instance, are killed at freezing temperatures of about Ϫ5°C, but after cold acclimation, can survive temperatures down to about Ϫ20°C. Determining what accounts for the differences in freezing tolerance between plant species and the molecular basis of cold acclimation is of basic scientific interest and has the potential to provide new approaches to improve the freezing tolerance of plants, an important agronomic trait.A recent advance in understanding cold acclimation in Arabidopsis was the discovery of the C-repeat/dehydration-responsive element binding factor (CBF) cold-response pathway (see Thomashow, 2001). Arabidopsis encodes a small fami...

RNA Expression Profiles and Data Mining of Sugarcane Response to Low Temperature

“…One SUCEST-assembled sequence showed similarity to CBF1 protein (Table III), including the nearly identical signature sequences (PPK/RPAGRxKFx-ETRHP and DSAWL) surrounding the AP2/EREBP domain, characteristic of CBF proteins (Jaglo et al, 2001). Gilmour et al (1998) suggested that CBF1 encodes the AP2-like transcriptional activator that binds to the CRT/DRE regulatory element present in the promoter of many COR genes and stimulates their transcription.…”

“…Recently, Jaglo et al (2001) identified components of the CBF regulon (DRE/CRT-containing genes that are induced by CBF transcription factors) in other plant species.…”

Tomato Plants Ectopically Expressing Arabidopsis CBF1 Show Enhanced Resistance to Water Deficit Stress

“…Once ice crystals form in the extracellular spaces of plant cells, water moves out of the cell resulting in water deficit. Therefore, the mechanisms of freezing and water deficit tolerance may be similar to each other (Thomashow, 2001). The freezing, salt, and drought tolerance capabilities of transgenic Arabidopsis have also been achieved by the expression of DREB1A (CBF3) cDNA, driven by a 35S promoter or stress-inducible RD29A promoter (Liu et al, 1998;Kasuga et al, 1999).…”

“…Overexpression of the CBF1 gene in Arabidopsis plants induces expression of COR genes and increases freezing tolerance in the absence of cold acclimation (Jaglo-Ottosen et al, 1998), suggestive of the role of a master switch of the CBF regulation (Thomashow, 2001). Besides its effect in Arabidopsis, overexpression of CBF1 in canola oilseed rape (Brassica napus) also activates COR homologous genes and enhances freezing tolerance, indicating that the function of CBF1 may be highly conserved in plants (Jaglo et al, 2001). Once ice crystals form in the extracellular 1 This work was supported by Academia Sinica (grant) and by the National Science Council of the Republic of China (grant no.…”

Characterization of a Cold Tolerance-related Gene, BrCSR, Derived from Brassica rapa

“…들이 활발히 진행되고 있다 (Dubouzet et al, 2003;Fowler and Thomashow, 2002;Jaglo et al, 2001;Lee et al, 2012;Qin et al, 2004;Seki et al, 2002;Yang et al, 2005;Zhang et al, 2006). 예를 들어, 벼에서는 GPAT(arabidopsis glycerol-3P-acyltransferase) (Yokoi et al, 1998), OsCDPK7(rice calciumdependent protein kinase) (Saijo et al, 2000), OsDREB1(rice DRE-binding protein 1) (Ito et al, 2006), HvCBF4(barley Crepeat binding factor) (Oh et al, 2007), OsCIPK03(rice calcineurin B-like protein-interaction protein kinase 03) (Xiang et al, 2007), 및 OsTPP1(trehalose-6-phosphate phosphatase) (Ge et al, 2008) 등이 있으며, 옥수수에서는 NPK1(nicotiana protein kinase) (Shou et al, 2004), 애기장대에서는 MYB15(MYB-like transcription factor) (Agarwal et al, 2006) 등이 대표적인 저 온 저항성 유전자들이다.…”