At a conference in Raleigh in February 2016, we presented a paper on the potential of Cas9-mediated gene drive systems for control of agricultural insect pests. At the meeting a draft manuscript was made available to attendees that described in more detail the ideas outlined in the presentation. The manuscript was subsequently revised, edited and is now available on line at the Journal of Responsible Innovation.
Our review of research advances over the past 25 years on the New World screwworm has been recently published in Entomologia Experimentalis et Applicata
Insect sexing strains that produce only males under certain conditions are highly advantageous for genetic control programs. If larval diet is a major cost for a mass rearing factory it is desirable if female insects die at early stages of development. For building such strains it would be ideal if the gene promoter used to drive a conditional transcription factor (e.g. tTA) was only active at the embryo stage. However, identifying such promoters is not a trivial exercise. In our recent paper in Scientific Reports we show that promoters that are active throughout development can be used to build sexing strains with most of the females dying at early larval stages.
Dr. Melina Florez-Cuadros recently joined the lab from the University of Nebraska-Lincoln where she studied the effects of temperature and diet in stable fly’s development. Melina is supported by the Dean’s Diversity Postdoctoral Fellowship from the College of Agriculture and Life Sciences at NCSU. She is developing site-specific recombination systems for making transgenic “male-only” strains of Lucilia cuprina.
Dr Kara Bolz recently joined the lab from UNC-Chapel Hill. Kara has studied epigenetic mechanisms in Arabidopsis and Drosophila and brings a wealth of experience in molecular genetics to the lab. Kara is supported by the BRAG grant to investigate the use of gene drive systems to suppress populations of pest insects, specifically spotted wing Drosophila and New World screwworm.
Dr. Bill Reid recently joined the lab from USDA-ARS, Gainesville where investigated promoters and tissue-specific genes in Ae. aegypti . For his doctoral studies at Auburn U., Bill took a functional genomics approach to study insecticide resistance in housefly and mosquito species. Bill is supported by the SCRI grant to develop male-only strains and better genetic tools for spotted wing Drosophila.
Our application for funding to develop transgenic strains of Lucilia sericata that are engineered to produce and secrete factors to promote wound healing has been funded by DARPA, starting 1 January. The grant will be used to support Dr Rebecca Linger, who was first author on the proof-of-concept paper published in 2016 in BMC Biotechnology.
Our paper on the development and evaluation of transgenic strains of the New World screwworm that carry a conditional female lethal gene has been published in BMC Biology. Over a 50 year period, the SIT was used to eradicate screwworm from North and Central America. SIT is more efficient if only sterile males are released but until now this has not been possible. The modified strains produce only males on diet that does not contain tetracycline. The strains are comparable to the current mass reared strain for several characteristics that influence production. Further the transgenic males were competitive with the wild type strain for mating with females. The transgenic strains could potentially lead to significant savings for the ongoing and any future SIT program.
Our application to develop and evaluate conditional split Cas9-mediated gene drive systems in spotted wing Drosophila and New World screwworm has been funded by NIFA’s Biotechnology Risk Assessment Grants Program. The funding will likely be used to support a postdoctoral fellow
HDAC4 is essential for memory in Drosophila and mammals. The current issue of Genetics features our paper showing that HDAC4 interacts with Ubc9, the sole SUMO E2-conjugating enzyme, during memory formation (web). This study should open new avenues for research on how long term memories are established. The study was led by Helen Fitzsimons, a former postdoc in the lab, and follows on previous work on HDAC4 and HDAC1 and long term memory in Drosophila.