Flowering time pathway (WP2625)

Hordeum vulgare

Barley (Hordeum vulgare L.), a cereal species with major economic and agricultural impact, is a facultative long-day plant, i.e. it flowers earlier in response to long days than to short days. Flowering time genes of the photoperiod, vernalization and circadian clock pathways are best studied in barley. The Ppd-H1 gene, a pseudo-response regulator gene, is thought to be key for flowering induction under long days. Further important genes which convey flowering in barley under both photoperiods are homologs of FLOWERING LOCUS T (FT) and CONSTANS (CO). Flowering in response to vernalization is economically important in temperate cereals like barley and wheat and is controlled by the interaction of Vrn-H1 and Vrn-H2.


Alex Pico , Martina Bluemel , Friederike Ehrhart , Eric Weitz , Lars Willighagen , and Egon Willighagen


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Hordeum vulgare



Pathway Ontology

signaling pathway


Label Type Compact URI Comment
HvCEN GeneProduct uniprot:K7QT26
HvLUX1 GeneProduct ena.embl:AK357505
VRN-H1 GeneProduct None MADS-box transcription factor
Chromosome: 5H
HvCO2 GeneProduct uniprot:Q8L581 Chromosome: 6H
HvCO9 GeneProduct None
HvFT2 GeneProduct uniprot:A0S6X4 Chromosome: 3H
HvCO1 GeneProduct None Chromosome: 7H
VRN-H3(HvFT1) GeneProduct None Chromosome: 7H
Ppd-H1(HvPRR7) GeneProduct None pseudo-response regulator gene
Chromosome: 2H
HvELF3(Eam8) GeneProduct None
HvFT4 GeneProduct None Chromosome: 2H
VRN-H2 GeneProduct None zinc finger motif and CCT domain
Chromosome: 4H
HvGI GeneProduct None


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