Objective  Biological functions and lateral branching transduction mechanism of RhMAX2A were investigated by cloning the cDNA and determining the after-decapitation expressions in tissues of Rosa hybrida.

  Methods  The cDNA sequence of RhMAX2A was cloned from hybrid tea rose Dianhong by RT-PCR for a bioinformatic analysis. The subcellular location of the gene was determined by transient transformation of PC1300s-RhMAX2A-GFP in tobacco leaves. After decapitating the plant, expressions of the gene in different organs were determined by qRT-PCR.

  Results   The cDNA of RhMAX2A (GeneBank accession number: OP055810) was 1030 bp in length encoding 246 amino acids with the chemical formula of C₂₉₁₀H₄₇₉₃N₁₀₂₉O₁₂₄₄S₂₁₀, a molecular weight of 27.35 kD, and a total atomic weight of 3909. The instability coefficient of the unstable hydrophilic protein was 53.07, the fat coefficient, 106.30, and the GRAVY value, 0.049. The protein secondary structure was mainly α-helix and random coil of a presumed F-box domain belonging to the α/β hydrolase family. RhMAX2A (OP055810) had the highest homology with that in R. chinensis Old Blush (XP_024283944.1) followed by that in Fragaria vesca subsp. vesca (XP_004287076.1) of the same closely related subfamily. The encoded protein was in the nucleus. The gene expressed most highly in the roots but also in the axillary buds, and nodes among tested organs. Decapitation on the plant significantly upregulated RhMAX2A in the roots and axillary buds.

  Conclusion   RhMAX2A was successfully cloned from R. hybrida Dianhong, which functioned in the nucleus, expressed mainly in the roots and axillary buds, and could be upregulated by plant decapitation.