TY - JOUR

T1 - Seed transcriptome annotation reveals enhanced expression of genes related to ros homeostasis and ethylene metabolism at alternating temperatures in wild cardoon

AU - Huarte, Hector R.

AU - Puglia, Giuseppe D.

AU - Prjibelski, Andrey D.

AU - Raccuia, Salvatore A.

PY - 2020/9

Y1 - 2020/9

N2 - The association among environmental cues, ethylene response, ABA signaling, and reactive oxygen species (ROS) homeostasis in the process of seed dormancy release is nowadays well-established in many species. Alternating temperatures are recognized as one of the main environmental signals determining dormancy release, but their underlying mechanisms are scarcely known. Dry after-ripened wild cardoon achenes germinated poorly at a constant temperature of 20, 15, or 10◦C, whereas germination was stimulated by 80% at alternating temperatures of 20/10◦C. Using an RNA-Seq approach, we identified 23,640 and annotated 14,078 gene transcripts expressed in dry achenes and achenes exposed to constant or alternating temperatures. Transcriptional patterns identified in dry condition included seed reserve and response to dehydration stress genes (i.e., HSPs, peroxidases, and LEAs). At a constant temperature, we observed an upregulation of ABA biosynthesis genes (i.e., NCED9), ABA-responsive genes (i.e., ABI5 and TAP), as well as other genes previously related to physiological dormancy and inhibition of germination. However, the alternating temperatures were associated with the upregulation of ethylene metabolism (i.e., ACO1, 4, and ACS10) and signaling (i.e., EXPs) genes and ROS homeostasis regulators genes (i.e., RBOH and CAT). Accordingly, the ethylene production was twice as high at alternating than at constant temperatures. The presence in the germination medium of ethylene or ROS synthesis and signaling inhibitors reduced significantly, but not completely, germination at 20/10◦C. Conversely, the presence of methyl viologen and salicylhydroxamic acid (SHAM), a peroxidase inhibitor, partially increased germination at constant temperature. Taken together, the present study provides the first insights into the gene expression patterns and physiological response associated with dormancy release at alternating temperatures in wild cardoon (Cynara cardunculus var. sylvestris).

AB - The association among environmental cues, ethylene response, ABA signaling, and reactive oxygen species (ROS) homeostasis in the process of seed dormancy release is nowadays well-established in many species. Alternating temperatures are recognized as one of the main environmental signals determining dormancy release, but their underlying mechanisms are scarcely known. Dry after-ripened wild cardoon achenes germinated poorly at a constant temperature of 20, 15, or 10◦C, whereas germination was stimulated by 80% at alternating temperatures of 20/10◦C. Using an RNA-Seq approach, we identified 23,640 and annotated 14,078 gene transcripts expressed in dry achenes and achenes exposed to constant or alternating temperatures. Transcriptional patterns identified in dry condition included seed reserve and response to dehydration stress genes (i.e., HSPs, peroxidases, and LEAs). At a constant temperature, we observed an upregulation of ABA biosynthesis genes (i.e., NCED9), ABA-responsive genes (i.e., ABI5 and TAP), as well as other genes previously related to physiological dormancy and inhibition of germination. However, the alternating temperatures were associated with the upregulation of ethylene metabolism (i.e., ACO1, 4, and ACS10) and signaling (i.e., EXPs) genes and ROS homeostasis regulators genes (i.e., RBOH and CAT). Accordingly, the ethylene production was twice as high at alternating than at constant temperatures. The presence in the germination medium of ethylene or ROS synthesis and signaling inhibitors reduced significantly, but not completely, germination at 20/10◦C. Conversely, the presence of methyl viologen and salicylhydroxamic acid (SHAM), a peroxidase inhibitor, partially increased germination at constant temperature. Taken together, the present study provides the first insights into the gene expression patterns and physiological response associated with dormancy release at alternating temperatures in wild cardoon (Cynara cardunculus var. sylvestris).

KW - Antioxidants

KW - Dormancy termination

KW - Environmental signals

KW - Ethylene signaling

KW - Gene expression

KW - RNA-Seq

KW - OXIDATION

KW - antioxidants

KW - MECHANISMS

KW - GERMINATION

KW - FLUCTUATING TEMPERATURES

KW - RESPONSES

KW - ethylene signaling

KW - dormancy termination

KW - ARABIDOPSIS SEEDS

KW - ABSCISIC-ACID

KW - TRAITS

KW - environmental signals

KW - DORMANCY ALLEVIATION

KW - gene expression

KW - SIGNALING NETWORKS

UR - http://www.scopus.com/inward/record.url?scp=85091185032&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/1b1347db-5260-3bbe-aeb6-10f62ddef91b/

U2 - 10.3390/plants9091225

DO - 10.3390/plants9091225

M3 - Article

AN - SCOPUS:85091185032

VL - 9

SP - 1

EP - 19

JO - Plants

JF - Plants

SN - 2223-7747

IS - 9

M1 - 1225

ER -