A transposition-active Phyllostachys edulis long terminal repeat (LTR) retrotransposon

Area of Science:

• Genetics
• Plant Biology
• Molecular Biology

Background:

• Moso bamboo (Phyllostachys edulis) breeding is challenging due to infrequent sexual reproduction.
• Insertional mutagenesis using active transposons offers an alternative strategy for developing new moso bamboo germplasm.

Purpose of the Study:

• To identify and characterize active endogenous retrotransposons in the moso bamboo genome.
• To investigate the transposition capability of a newly identified retrotransposon, PHRE2, and its response to environmental stimuli.

Main Methods:

• Identification of full-length LTR retrotransposons using LTR-STRUC.
• Bioinformatic analysis of retrotransposon structure and domains.
• Transposition assays in Arabidopsis thaliana and moso bamboo under various treatments (tissue culture, irradiation, plant hormones).

Main Results:

• A full-length intact LTR retrotransposon, named PHRE2 (Phyllostachys edulis retrotransposon 2), was identified in the moso bamboo genome.
• PHRE2 possesses all necessary domains for transposition and shows high similarity between its LTR sequences.
• PHRE2 copy number increased in Arabidopsis T3 generation plants and in moso bamboo seedlings treated with tissue culture, irradiation, or plant hormones, indicating inducible transposition.

Conclusions:

• PHRE2 is an active LTR retrotransposon in moso bamboo with the capacity for transposition.
• Environmental conditions can induce the transposition of PHRE2, suggesting its potential utility in moso bamboo genetic improvement and germplasm creation.