Molecular Analysis of the Alpha-Tubulin Gene from the Microsporidium, Endoreticulatus sp. Zhenjiang, Isolated from Bombyx mori

Yajie Yue,Zhongyuan Shen,Xudong Tang,Shengyan Xiao,Wei Wang,Xuliang Fu,Li Xu,Nan Li

doi:10.4236/as.2014.510095

Abstract

We isolated a microsporidium from the silkworm, Bombyx mori, and classified it as Endoreticulatus sp. Zhenjiang based on morphological characteristics and phylogenetic analyses of ribosomal sequences. This microsporidium causes silkworm pebrine, although its original host and mode of transmission are unknown. To better understand its distribution and transmission mode, it is essential to have species specific molecular markers. Towards this goal, we characterized the alpha tubulin gene from Endoreticulatus sp. Zhenjiang in this study. The full-length alpha-tubulin cDNA from Endoreticulatus sp. Zhenjiang was cloned and sequenced (GenBank ID: KJ784483) using the rapid amplification of cDNA ends (RACE) protocol. The alpha-tubulin cDNA is 1382 bp long with an open reading frame spanning 1320 bp and consisting of a short 20-bp 5’-untranslated region (5’-UTR) and a 42-bp 3’-UTR with a stop codon and a poly (A) tail. This alpha-tubulin cDNA encodes a deduced polypeptide with 439 amino acids, including a complete tubulin domain and a tubulin C domain. This protein has an estimated isoelectric point of 5.1 and a predicted molecular weight of 48.6 kDa.

Highlights

Microsporidia are unicellular eukaryotes and obligate intracellular parasites with the ability to infect a broad spectrum of hosts from protists to mammals, including humans and have worldwide distribution [1] [2]
We have identified an Endoreticulatus microsporidium, which was isolated from silkworm in Zhenjiang City, Jiangsu Province, China
The results showed that the expected fragment was amplified only from the genomic DNA of Endoreticulatus sp

Summary

Introduction

Microsporidia are unicellular eukaryotes and obligate intracellular parasites with the ability to infect a broad spectrum of hosts from protists to mammals, including humans and have worldwide distribution [1] [2]. Nosema bombycis is the first described microsporidium, which prevailed in Europe, America, and Asia during the mid-19th century. It is recognized as the pathogen of silkworm pebrine and still causes heavy economic losses in silk-producing countries such as China [5]. Besides Nosema, several microsporidian genera, such as Pleistophora, Thelohania, Vairimorpha, and Endoreticulatus have been found to infect silkworm. The organization of the rRNA gene was 5’-LSU-ITS-SSU-IGS-5S-3’, which is reverse compared to the organization of most microsporidian rRNA regions. This is the first Endoreticulatus microsporidium with a reversed rRNA gene arrangement [7]

Methods

Findings

Discussion

Conclusion