Decoding the molecular codes of Host Seeking Behaviour in Indian Malarial Vectors; PI: Rajnikant Dixit, Ph.D.

Name of Grantee & Logo:

ICMR-National Institute of Malaria Research

Objective of the Project:

In the current investigation, we aimed to decode and identify the key neuro-olfactory genetic factors, which regulate the complex prior- and post-blood meal events of host seeking and ovioposition, from Indian malarial parasites Anopheles culicifacies and An. stephensi. This will enable researchers to understand how mosquitos succeed in finding, searching and locating a human host from a distance of at least ~400m away and suck blood within 2 minutes.

Impact Factor or Potential:

Unlocking the mystery of how mosquitoes manage complex host- seeking and blood-feeding behavioural events, may lead to identifying crucial genetic factors, valuable to manipulate and design new molecular tools to disrupt mosquito-human bite exposure, in the near future.

Achievement so far:

Through modern next-generation sequencing technology, we successfully decoded, identified and compared the molecular changes occurring in olfactory system of the pre- and post- blood-fed female mosquito Anopheles culicifacies. Notably, we unravelled:

  • Mosquito olfactory encodes two major family proteins named Odorant Binding Proteins (OBPs) and their Odorant Receptors (Ors)
  • Olfactory encoded Sensory Appendage Proteins (SAP), a family member of OBPs, are unique to regulate the host-seeking behaviour at late night
  • Synergistic action of odorant binding proteins (OBPs) and Odorant receptors (Ors) manages host-seeking and blood-feeding behaviour
  • Fig. 1.

    Proposed hypothesis to decode the evolutionary specialty of host-seeking and blood-feeding behaviour in the adult female mosquitoes

    Fig. 2.

    Fine scale decoding of the molecular secretes that adult females are smart enough to regulate olfactory encoded OBPs and Ors action synergistically to guide and mange host-seeking and blood-feeding behavioural responses