Cloning and Expression Analysis of Actin Gene from Narcissus tazetta var.chinensis

Based on a fragment cDNA from different florescence suppression subtractive hybridization (SSH) of Narcissus tazetta var. chinensis,an actin gene NtACT1 was separated and cloned by RACE and RT-PCR. The NtACT1 cDNA is 1 448 bp,containing a 1 134 bp ORF,encoding a protein of 377 amino acid with a predicted molecular mass of 41.66kD and theoretical isoelectric point of 5.31. Phylogenetic analysis showed that the NtACT1 was clustered together with actin4 and actin12 from which were reproductive actin isovariants. Genetic relationship of NtACT1 is closest with actin of Platycodon grandiflorus (AEF58501),next with actin of Mangifera indica (AEO45960) and Gossypium hirsutum (AAC31886),and farther with actin from Narcissus tazetta var. chinensis (AEM89276). Semi-quantitative RT-PCR revealed that NtACT1 could express at similar level in root,leaf,scape,petal,corolla,stamen and pistil.Therefore,NtACT1 might be constitutive expression actin gene.