Characterization of GA20ox genes in tall and dwarf types coconut (Cocos nucifera L.)

Abstract

Coconuts (Cocos nucifera L.) are divided by the height into tall and dwarf types. In many plants the short phenotype was emerged by mutation of the GA20ox gene encoding the enzyme involved in gibberellin (GA) biosynthesis. Two CnGA20ox genes, CnGA20ox1 and CnGA20ox2, were cloned from tall and dwarf types coconut. The sequences, gene structures and expressions were compared. The structure of each gene comprised three exons and two introns. The CnGA20ox1 and CnGA20ox2 genes consisted of the coding region of 1110 and 1131 bp, encoding proteins of 369 and 376 amino acids, respectively. Their amino acid sequences are highly homologous to GA20ox1 and GA20ox2 genes of Elaeis guineensis, but only 57% homologous to each other. However, the characteristic amino acids two histidines and one aspartic acid which are the two iron (Fe) binding residues, and arginine and serine which are the substrate binding residues of the dioxygenase enzyme in the 20G-FeII_Oxy domain involved in GA biosynthesis, were found in the active site of both enzymes. The evolutionary relationship of their proteins revealed three clusters in vascular plants, with two subgroups in dicots and three subgroups in monocots. This result confirmed that CnGA20ox was present as multi-copy genes, and at least two groups CnGA20ox1 and CnGA20ox2 were found in coconut. The nucleotide sequences of CnGA20ox1 gene in both coconut types were identical but its expression was about three folds higher in the leaves of tall coconut than in those of dwarf type which was in good agreement with their height. In contrast, the nucleotide sequences of CnGA20ox2 gene in the two coconut types were different, but the expression of CnGA20ox2 gene could not be detected in either coconut type. The promoter region of CnGA20ox1 gene was cloned, and the core promoter sequences and various cis-elements were found. The CnGA20ox1 gene should be responsible for the height in coconut, which is different from other plants because no mutation was present in CnGA20ox1 gene of dwarf type coconut.

Genome-wide identification and characterization of gibberellin metabolic and signal transduction (GA MST) pathway mediating seed and berry development (SBD) in grape (Vitis vinifera L.)

“…VvGA3oxs and VvGA20oxs are particularly important in controlling bioactive GA levels [ 19 ], and VvGA2oxs modulate the endogenous GA balance by GA inactivation. In the present study, VvGA20oxs , VvGA3oxs and VvGA2oxs were multicopy genes and exhibited temporal-specific expression pattern in berries, which agree with the studies on rice [ 20 ] and Arabidopsis [ 21 ]. Field observations and few physiological studies [ 22 ] point out that grape SBD are strictly correlated, and seeds are generally a metabolic center of phytohormones [ 23 ].…”

Cloning and Expression Analysis of After-Ripening Related Genes in Panax ginseng Seed

“…e expression level of GA20ox (GA synthetic gene) in the physiological afterripening stage was higher than that in the morphological after-ripening stage, which proved that low temperature could promote GA synthesis and increase expression of GA synthetic gene, which is consistent with the results of Derkx [24]: low temperature can enhance expression of AtGA20ox1 and AtGA20ox1.…”

A SNP variation in an expansin (EgExp4) gene affects height in oil palm

“…These gene variations were first elucidated by PacBio sequencing and only the SNP markers were genotyped and analyzed for height association. These genes were targeted because of their reported relation to height ( Boonkaew et al, 2018 ; Choi, Kim & Kende, 2004 ; Lee et al, 2015 ; Pootakham et al, 2015 ; van der Knaap, Kim & Kende, 2000 ). In oil palm, height QTLs on chromosome 10, 14 and 15, control 10–21% of phenotype variance expected (PVE) for height.…”

“…As mentioned above, we targeted EgDELLA1 (DELLA), EgAPG1 (asparagine synthase) and EgGRF1 (growth regulating factor). The other genes, EgGA20ox1 (gibberellin 20 oxidase) and EgExp4 (expansin), were targeted as height-related genes in other species, including coconut ( Boonkaew et al, 2018 ) and rice ( Choi, Kim & Kende, 2004 ).…”