Molecular Cloning and Functional Analysis of UDP N-acetylglucosamine Pyrophosphorylases Gene in Frankliniella occidentalis

  Objective  Effects of UDP N-acetylglucosamine pyrophosphorylases (UAP) on the growth and development of Frankliniella occidentalis were studied.

  Method  Based on a transcriptome dataset, an open reading frame (ORF) of UAP gene of F. occidentalis (FoccUAP) was cloned. Expressions of the FoccUAP in different body tissues and growth stages of the insect were detected by RT-qPCR. Effects of UAP gene on the growth and development were examined by microinjecting dsRAN in the 2^nd instars (eclosion about 24 h) of F. occidentalis.

  Result  The full-length of FoccUAP ORF was 1 545 bp and encoded 514 amino acids with a predicted molecular mass of 56.738 kDa. FoccUAP contained the conserved domain of glyco-tranf-GTA-type super family, which had a close evolutionary relationship with the orthologues in Isoptera, Blattaria, Orthoptera, and Hemiptera. The RT-qPCR results showed that FoccUAP was highly expressed in the head and abdomen, detected in the antenna, thorax and leg, and found in all developmental stages of the insect. The relative transcript levels of FoccUAP in the 2^nd instar, pupa, adult-24 h, adult-48 h, adult-168 h, and adult-240 h were 1.30-, 2.50-, 1.56-, 2.0-, 2.43-, and 2.56-fold, respectively, of those in the 1^st instar. Further examination on the RNAi showed that the injection of dsUAP into the 2^nd instar F. occidentalis significantly decreased the eclosion rate (36.3%) and the survival rate (5.0% in 120 h after microinjection) as compared to dsGFP controls. Moreover, the dsUAP treatment also induced abnormal phenotypes on wings and abdomen–thorax of the thrips.

  Conclusion  UAP played a significant role in the growth and development of F. occidentalis.