The lethal giant larvae gene in Tribolium castaneum: molecular properties and roles in larval and pupal development as revealed by RNA interference.

Da Xiao,Kun Zhu,Jianxiu Yao,Xiwu Gao,Xiao Liang

doi:10.3390/ijms15046880

Abstract

We identified and characterized the TcLgl gene putatively encoding lethal giant larvae (Lgl) protein from the red flour beetle (Tribolium castaneum). Analyses of developmental stage and tissue-specific expression patterns revealed that TcLgl was constitutively expressed. To examine the role of TcLgl in insect development, RNA interference was performed in early (1-day) larvae, late (20-day) larvae, and early (1-day) pupae. The early larvae injected with double-stranded RNA of TcLgl (dsTcLgl) at 100, 200, and 400 ng/larva failed to pupate, and 100% mortality was achieved within 20 days after the injection or before the pupation. The late larvae injected with dsTcLgl at these doses reduced the pupation rates to only 50.3%, 36.0%, and 18.2%, respectively. The un-pupated larvae gradually died after one week, and visually unaffected pupae failed to emerge into adults and died during the pupal stage. Similarly, when early pupae were injected with dsTcLgl at these doses, the normal eclosion rates were reduced to only 22.5%, 18.0%, and 11.2%, respectively, on day 7 after the injection, and all the adults with abnormal eclosion died in two days after the eclosion. These results indicate that TcLgl plays an essential role in insect development, especially during their metamorphosis.

Highlights

Cell polarity, which refers to spatial differences in the shape, structure, and function of cells, is fundamental to cellular life and essential for generating cell diversity for all eukaryotic cells [1,2]
The full-length of TcLgl cDNA contains 3522 base pairs, including an open reading frame (ORF) of 3315 bp that encodes a protein of 1105 amino acid residues, and 68- and 136-nucleotide non-coding regions at the 5'- and 3'-ends, respectively (Figure 1)
We found considerable suppressions of TcLgl transcript in all the larvae injected with the double stranded RNA of TcLgl at each of the three doses (100, 200, and 400 ng/larva) as compared with the control larvae injected with the dsRNA of GFP (400 ng/larva) on days 2, 4, 6, and 8

Summary

Introduction

Cell polarity, which refers to spatial differences in the shape, structure, and function of cells, is fundamental to cellular life and essential for generating cell diversity for all eukaryotic cells [1,2]. It is essential for various processes including cell division, cell migration, lymphocyte homing and the conduction of nerve impulses [3]. Three different conserved polarity protein complexes, including the Par, the Crumbs and the Scrib, have been identified.

Results

Discussion

Conclusion