关键词: 卷丹, LlAGO1, 腋生珠芽, 克隆, 表达

Abstract:

In this study，AGO1 gene was isolated from the leaf axil of Lilium lancifolium by using reverse transcription PCR（RT-PCR） and rapid-amplification of cDNA ends（RACE）techniques，and was named as LlAGO1. The full length cDNA of LlAGO1 was 4 014 bp，which contained a 3 687 bp complete open reading frame（ORF）and encoded 1 228 amino acid residues with a predicted molecular weight of 135.36 kD，bioelectric point value of 9.57. Amino acid sequence analysis showed that it contains two conserved domains named PAZ and Piwi. Signal peptide prediction indicated that LlAGO1 without signal peptide and was a secreted protein. LlAGO1 was predicted to locate in the nuclear. In the phylogenetic tree，LlAGO1 has the closest evolutionary relationship with the homologous protein from Asparagus officinalis（XP_020260210.1）. The qRT-PCR analysis showed that LlAGO1 expressed in most of the tested tissues，but mainly occurred in leaf axil，and the lowest in leaf and root. During the process of axillary bulbil formation，LlAGO1 gene only expressed in the upper leaf axils which were able to generate bulbils and the expression was the highest at S3 stage，but didn’t express in the lower leaf axils which could not form bulbils，which implied that this gene might play an important role in regulating the formation of axillary bulbils.

Key words: Lilium lancifolium, LlAGO1, axillary bulbil, cloning, expression