Compositions and methods for insect control
View Patent ↗Described herein are expression vectors encoding the Wolbachia protein WalE1. Also described are insects transformed with an expression vector of the present disclosure, and progeny thereof. Also described are methods for improving Wolbachia replication and transmission in its insect host by overexpressing WalE1 in the insect host. Improved Wolbachia replication and transmission provides for insect population control and pathogen resistance in insects, which can reduce disease transmission.
1 . A method to control a native mosquito population, the method comprising the steps of:
a) generating a population of transgenic Wolbachia -infected mosquitos, wherein the mosquitos are transformed with a vector comprising a polynucleotide that encodes Wolbachia actin localizing effector 1 (WalE1) or a functional fragment of Wal E1 operably linked to an expression control sequence and wherein the overexpression of WalE1 is greater than a mosquito harboring Wolbachia but lacking the vector comprising the polynucleotide that encodes Wolbachia actin localizing effector 1 (WalE1) or the functional fragment of WalE1 operably linked to the expression control sequence;
b) crossing the transgenic Wolbachia -infected female mosquitos with male mosquitos of a native mosquito population, wherein the Wolbachia -infected female mosquitos (i) are from the population of transgenic Wolbachia -infected mosquitos that overexpress (WalE1) polypeptide, or (ii) are progeny of the population of transgenic Wolbachia -infected male mosquitos that overexpress the WalE1 polypeptide;
c) generating a progeny mosquito population from the cross, wherein the progeny are capable of greater Wolbachia loads compared to a female mosquito of the native mosquito population; and
d) releasing the Wolbachia -infected male progeny mosquitos to mate with Wolbachia -uninfected female mosquitos in the native mosquito population, thereby producing unviable progeny and controlling the native mosquito population.
2 . A method according to claim 1 , where the WalE1 polypeptide has an amino acid sequence that is at least 90% identical to the amino acid sequence of wMel WalE1 protein (SEQ ID NO: 2).
3 . A method according to claim 1 , where the WalE1 polypeptide has an amino acid sequence that is SEQ ID NO: 2.
4 . A method according to claim 1 , where the native mosquito population comprises mosquitos belonging to the family Culicidae.
5 . A method according to claim 1 , where the native mosquito population comprises mosquitos belonging to a genus selected from the group consisting of Anopheles, Aedes , and Culex.
6 . A method according to claim 1 , where the Wolbachia -injected male mosquitos are infected with one or more strains of Wolbachia pipientis.
7 . A method according to claim 1 , where the expression control sequence is expressible in an insect.
8 . A method according to claim 1 , wherein the mosquitos transformed are already infected by Wolbachia.
9 . A method according to claim 1 , wherein steps b) and c) are repeated one ore more times prior to the releasing step d).
10 . A method of generating a mosquito population capable of greater Wolbachia infection loads, the method comprising the steps of:
a) generating a population of transgenic Wolbachia -infected mosquitos, wherein the mosquitos are transformed with a vector comprising a polynucleotide that encodes Wolbachia actin localizing effector 1 (WalE1) or a functional fragment of Wal E1 operably linked to an expression control sequence and wherein the overexpression of WalE1 is greater than a mosquito harboring Wolbachia but lacking the vector comprising the polynucleotide that encodes Wolbachia actin localizing effector 1 (WalE1) or the functional fragment of Wal E1 operably linked to the expression control sequence;
b) crossing the transgenic Wolbachia -infected male mosquitos with a female mosquito of a native mosquito population, wherein the Wolbachia -infected male mosquitos (i) are from the population of transgenic Wolbachia -infected mosquitos that overexpress (WalE1) polypeptide, or (ii) are progeny of the population of transgenic Wolbachia -infected male mosquitos that overexpress the WalE1 polypeptide;
c) generating a progeny mosquito population from the cross, wherein the progeny are capable of greater Wolbachia loads compared to a female mosquito of the native mosquito population.