- Author: Kathy Keatley Garvey
Host is Michael Parrella, professor and chair, Department of Entomology and Nematology.
"Many species groups, including mammals or many insects, determine sex using heteromorphic sex chromosomes," Bachtrog says in her abstract. "Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (5 large rods and a small dot), but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 35 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies.
"We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with homomorphic sex chromosomes, others were a different chromosome replaced the dot as a sex chromosome, or were up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes). Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through upregulation of the single X in males. Yet, X chromosomes generally show a deficiency of genes with male-biased expression, presumably reflecting sex-specific selection pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner, and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa."
Bachtrog writes on her website: "Research in our lab combines both computational and experimental approaches to address a broad range of topics in Evolutionary and Functional Genomics including: (1) Determining the evolutionary benefits of sex and recombination (2) Investigations of large scale changes in patterns of gene expression on evolving sex chromosomes: Dosage compensation of X-linked genes and silencing of Y-linked genes by heterochromatin formation (3) Comparative & functional genomics of young Y chromosomes in Drosophila and mammals (4) Sexual antagonistic variation and feminization & masculinization of evolving X chromosomes (5) Quantifying the mode and strength of selection acting on coding and non-coding DNA in the Drosophila genome (6) Population genetics of Tetrahymena thermophila." (See lab research)
Bachtrog received her master's degree in genetics in 1999 from the University of Vienna, graduating with high honors. She obtained her doctorate in genetics in 2002 from the University of Vienna, Austria, and University of Edinburgh, UK, , graduating with high honors. She completed a postdoctoral fellowship in the Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, UK, from 2002 to 2003, and then was an Austrian Academy of Science Fellow (2003-2005) at Cornell University, Ithaca, N.Y.
Bachtrog's first faculty appointment was as assistant professor, 2005-2008, at UC San Diego's Division of Biological Sciences. She joined UC Berkeley in 2008, serving as an assistant professor, 2008-2012, in the Department of Integrative Biology, Center for Theoretical Evolutionary Genomics. Bachtrog was promoted to associate professor in 2012.
Among the recent awards and honors she's received:
- Packard Fellowship in Evolutionary Biology, David and Lucile Packard Foundation (2008)
- Sloan Research Fellowship in Computational and Evolutionary Molecular Biology, Alfred P. Sloan foundation (2007)
- Young Investigator Prize for Most Promising Young Researcher, The American Society of Naturalists (2004)
- Austrian Academy of Science, Austrian Programme for Advanced Research and Technology fellowship (2003)
- The Royal Society, Royal Society Research Grant (2002)
The remainder schedule of seminars:
Wednesday, Dec. 3
No seminar
Wednesday, Dec. 10
Sawyer Fuller
Postdoctoral researcher, Harvard University
Title: "RoboBee: Using the Engineering Toolbox to Understand the Flight Apparatus of Flying Insects"
Host: James Carey, distinguished professor of entomology
This seminar is being remote broadcast to UC Davis via internet
Contacts:
Steve Nadler, sanadler@ucdavis.edu
Professor, UC Davis Department of Entomology and Nematology
Jesael "Jesa" David, jcdavid@ucdavis.edu
Student Affairs Officer, Graduate Programs
Plant Pathology, Entomology and Nematology