Identification of a gustatory receptor tuned to sinigrin in the cabbage butterfly Pieris rapae

PLoS Genet. 2021 Jul 15;17(7):e1009527. doi: 10.1371/journal.pgen.1009527. eCollection 2021 Jul.

Abstract

Glucosinolates are token stimuli in host selection of many crucifer specialist insects, but the underlying molecular basis for host selection in these insects remains enigmatic. Using a combination of behavioral, electrophysiological, and molecular methods, we investigate glucosinolate receptors in the cabbage butterfly Pieris rapae. Sinigrin, as a potent feeding stimulant, elicited activity in larval maxillary lateral sensilla styloconica, as well as in adult medial tarsal sensilla. Two P. rapae gustatory receptor genes PrapGr28 and PrapGr15 were identified with high expression in female tarsi, and the subsequent functional analyses showed that Xenopus oocytes only expressing PrapGr28 had specific responses to sinigrin; when ectopically expressed in Drosophila sugar sensing neurons, PrapGr28 conferred sinigrin sensitivity to these neurons. RNA interference experiments further showed that knockdown of PrapGr28 reduced the sensitivity of adult medial tarsal sensilla to sinigrin. Taken together, we conclude that PrapGr28 is a gustatory receptor tuned to sinigrin in P. rapae, which paves the way for revealing the molecular basis of the relationships between crucifer plants and their specialist insects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brassica
  • Butterflies / drug effects
  • Butterflies / physiology*
  • Drosophila / genetics
  • Female
  • Gene Expression Regulation
  • Glucosinolates* / pharmacology
  • Insect Proteins / genetics
  • Insect Proteins / metabolism*
  • Larva
  • Oocytes / metabolism
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism*
  • Taste Perception
  • Xenopus

Substances

  • Glucosinolates
  • Insect Proteins
  • Receptors, Cell Surface
  • sinigrin

Grants and funding

This work was supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDPB16; URL: www.cas.cn) to CZW, and the National Natural Science Foundation of China (Grant No. 31830088 and 31772528; URL: www.nsfc.gov.cn) to CZW. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.