6/1/2015 Volume 7 Issue 11

Research TipsVice Chancellor for Research: RJ Traystman

DR. T'S CORNER

Gene turns female mosquitoes into malesThe female of the species is more deadly

than the male, the famed author RudyardKipling wrote, and that's certainly true for themosquito Aedes aegypti, also known as theyellow fever mosquito. Only females feast onhuman blood, transmitting not only yellowfever but also dengue and several otherdiseases. Imagine if you could turn all mosquitoes into males? That's apossibility raised by new research that pinpoints the gene thatdetermines whether a mosquito becomes male.

Researchers have known for decades that at least one gene thatmakes A. aegypti embryos male resides on a stretch of DNA onchromosome 1. They named that region the M locus, but until now theywere unable to pinpoint the specific gene. Part of the problem was thatthe region contains large amounts of repetitive DNA, making it difficult tosequence that region.

To find the gene, scientists sequenced thousands of pieces of DNAfrom male and female mosquitoes belonging to two different strains of A.aegypti and looked for stretches that were more common in males ofboth strains. They found 164 such sequences and matched them againstdata showing what genes are active in embryos, looking for sequencesthat seemed to be active in early male embryos. In the 24 sequences thatremained, they found one new gene, which they named Nix. About halfof the female embryos injected with a piece of DNA containing that genedeveloped male genitals.

This interesting basic science has potential for genetic controlstrategies. One application would be to help with control strategies thatalready exist to produce mosquitoes that carry a lethal gene that killsoffspring in early development, which can drastically reduce mosquitopopulations. But half the mosquitoes produced are females that cannotbe released, because they could themselves help spread the diseasesthey are designed to combat. The whole system would be more efficientif you could produce only males.

However, scientists need to show that they can accomplish full sexconversion. Only some females became male in the study, because theNix gene needs to be integrated into the genome of the mosquitoes forthe protein to be produced in sufficient quantities.

That could lead to another strategy. Scientists recently reported asystem that allows them to push a certain gene into the next generationat almost 100% frequency. Coupling the Nix gene to such a system wouldessentially create a chain reaction spreading the male gene. If you releasesuch an animal, it only produces males until eventually the populationcrashes. But it is far too early to apply such a technique. We need thetechnology to control these systems before that can be used.

COLORADO MULTI INSTITUTIONAL REVIEWBOARD (COMIRB)

Establishing Recruitment Database ProtocolsAre you asking your subjects if you can contact them for

future studies? Are you creating a recruitment database underyour current protocol? If so, please read on.

If you plan on storing subject's identifiers for the purpose ofre-contacting at a later date for future studies, COMIRB stronglyrecommends you open a separate recruitment databaseprotocol that can remain open for future use. This is a relativelynew position adopted by COMIRB due to the increasing numberof sample- and data-banking proposals. Typically, if you keepsubjects' identifiers (e.g., name, email address, phone number)to contact him/her for future studies, you are also keepinghealth-related information in the recruitment database todetermine eligibility for a future study. Depending on the typeof recruitment database, the health-related information couldbe as simple as 'Type 2 Diabetes Mellitus' or include moredetailed information related to disease progression.

The problem with not establishing a separate recruitmentdatabase protocol is that you are not allowed to keep theinformation in the database once your current study is closed.The recruitment database under your current study must bedestroyed with study closure per the destruction plan specifiedunder the original study. If you wish to keep informationcollected in the recruitment database under each original study,you must transfer all the information to a separate recruitmentdatabase protocol prior to closing your current study.

Better yet, if you already have an established recruitmentdatabase protocol, your subjects can be referred to thatrecruitment database protocol once they agree to be contactedfor future studies. They will then go through a separate consentand HIPAA authorization process for the recruitment databaseprotocol.

If you are accessing the recruitment database createdunder an already closed study, COMIRB requests you establish arecruitment database protocol as soon as possible. If you haveany questions, please contact us for assistance (303-724-1055).

RESEARCH CORNER

Christopher Phiel, PhD, received his BS inBiology from Ursinus College and his PhD fromThomas Jefferson University. He did a Postdocat the University of Pennsylvania as a HowardHughes Fellow. He is an Assistant Professor inthe Department of Integrative Biology atUCDenver, recently had a manuscript acceptedin the journal Molecular Biology Christopher Phiel, PhDof the Cell entitled "Glycogen Synthase Kinase-3 (Gsk-3) Plays AFundamental Role In Maintaining DNA Methylation At ImprintedLoci In Mouse Embryonic Stem Cells." Previous studies from thePhiel laboratory had shown that DNA methylation was reduced inmouse embryonic stem cells (ESCs) in which both glycogensynthase kinase-3 isoforms (Gsk-alpha and Gsk-3beta) weregenetically deleted (double knockout; Gsk-3 DKO). This effect is dueto reduced expression of the de novo DNA methyltransferaseDnmt3a2, and is via an N-myc-dependent mechanism. SinceDnmt3a2 was known to methylate imprinted genes, his labortaoryexamined and found reductions in DNA methylation at twoimprinted loci. The current Manuscript, in collaboration withscientists from Thermo Fisher Scientific, further extends thesefindings to the entire genome. By performing methyl-seq on bothwild-type and Gsk-3 DKO ESCs, he was able to compare themethylation status across the genome and identify regions that arehypomethylated in the Gsk-3 DKO ESCs. Consistent with theprevious data, he finds that 77% of known imprinted loci havereduced DNA methylation in Gsk-3 DKO ESCs. Additionally, whencombined with microarray data examining gene expression, hefound a significant overlap between hypomethylated genes andthose exhibited significant changes in gene expression. His findingsclearly demonstrate a role for Gsk-3 in maintenance of DNAmethylation at imprinted loci, and extend the effects ofGsk-3-dependent signaling into epigenetics. The Phiel laboratory iscontinuing its investigations into the biology of Gsk-3 since thisenzyme has been implicated in numerous human diseases, such asbipolar disorder and Alzheimer's disease.

OFFICE OF RESEARCH DEVELOPMENT ANDEDUCATION (ORDE)

New NIH Biosketch FormatAs of May 25th, the NIH is requiring applicants to use the new

biosketch format, and below are some resources to help you makethe transition to the new format.

The NIH posted their latest announcement about the biosketchin December of last year. These are the biggest biosketch changes:

The page limit has gone from four to five pages.The format includes a contributions section where applicants canlist up to five major contributions.The contributions section expands the ways the applicant is ableto show the significance of their work and their contributions.Applicants will be able to include a link to all of their publications.

To learn more, please visit ORDE's blog:http://orde-cu.blogspot.com/2015/03/new-biosketch-format-for-nih.html

INSTITUTIONAL BIOSAFETY COMMITTEE (IBC)

Vaccine Clinical Trial Exemption from the NIH GuidelinesIf you are considering being the principal investigator for a vaccine

clinical trial, please be aware that in addition to the COMIRB approvalprocess, you may also need to have the University's InstitutionalBiosafety Committee (IBC) review and approve the clinical trial. TheNIH Guidelines for Research Involving Recombinant or Synthetic NucleicAcid Molecules, Appendix M, requires that research have the local IBCreview and approval before enrolling human subjects. Appendix Mapplies when the research involves the transfer of recombinant orsynthetic nucleic acid molecules into human research participants andhas extensive criteria for IBC consideration. However, if all of thefollowing three conditions are met the trial can be exempt from reviewby the NIH and from certain reporting requirements in Appendix M-I:1. The major goal is the induction or enhancement of an immuneresponse to a vector-encoded microbial immunogen2. Such an immune response has been demonstrated in modelsystems3. The persistence of the vector-encoded immunogen is not expected

Even if the trial meets these conditions, the UCD IBC is still requiredto review the research using Appendix M criteria.

Since the vaccine exemption was intended to streamline thedevelopment of new vaccines against infectious diseases, it does notextend to trials such as:1. The principal goal of the study is to treat a precancerous orcancerous lesion2. Administration of a microbial immunogen in combination withrecombinant DNA that encodes for a cytokine or other immunestimulant, for example recombinant interleukin-2, because therecombinant DNA encoding the cytokine is not of microbial origin.Reference:http://osp.od.nih.gov/faq/faqs-about-vaccine-exemption-nih-guidelines-research-involving-recombinant-dna-molecules

INSTITUTIONAL BIOSAFETY COMMITTEE(IBC)

We are currently recruiting additional members for theInstitutional Biosafety Committee (IBC). The IBC providesreview of all recombinant DNA research conducted atUCDenver. We particularly need additional MD membersfor the IBC to assist with the review and approval of humansubjects clinical trials involving recombinant DNA, viralvectors, or DNA vaccines. The IBC meets once per month;treats are provided! If you are interested in this opportunityfor University community service, please contact MarkDouse at 303-724-1057.