Barbara J. Meyer
Barbara J. Meyer (born 1949) is a biologist and genetist, noted for her pioneering research on lambda phage, a virus that infects bacteria; discovery of the master control gene involved in sex determination; and studies of gene regulation, particularly dosage compensation. Meyer’s work has revealed mechanisms of sex determination and dosage compensation—that balance X-chromosome gene expression between the sexes in "Caenorhabditis elegans" that continue to serve as the foundation of diverse areas of study on chromosome structure and function today. Dr. Meyer is an HHMI investigator, a genetics, genomics and development professor at UC  Berkeley, and an adjunct professor in the biochemistry and biophysics department at University of California, San Francisco (UCSF)'s School of Medicine. Her current research focuses on the molecular networks controlling dynamic chromosome behaviors during cell development which endure genome stability. Biography. Meyer is a native Californian, born and raised in Stockton. Meyer completed her undergraduate BS at Stanford University, working with David Clayton. She began her Ph.D. at the University of California, Berkeley and completed her graduate studies in 1979 at Harvard University in the lab of Mark Ptashne, working on gene regulation in lambda phage, a bacterial virus  which infects bacteria E. coli. During her postdoctoral period at Cambridge University and the MRC, Meyer begun her research on how chromosomes determine sex at the laboratory of Sydney Brenner, who later won a Nobel Prize for establishing the nematode worm "Caenorhabditis elegans" as an important model organism for research on development. Switching from virus to "Caenorhabditis elegans (C. elegans)", a roundworm, Meyer still studies gene regulation, but turning to sex determination. Meyer discovered the master gene involved in sex determination. Meyer's early work focused on how "C. elegans" “counts” the number of X chromosomes and sets of autosomes  to determine its sex, as well as how it adjusts to the imbalance in the number of X chromosomes between the two sexes. In "C. elegans", individuals with two X chromosomes are self-fertilizing hermaphrodites; those with only one X chromosome are males. A popular hypothesis when Meyer began her postdoctoral work was that the worms compensate for the difference in the number of copies of genes on the X chromosome between the two sexes. But it wasn’t clear whether the worms accomplished this by upregulating genes on the X chromosome in males or by downregulating genes on the  X chromosome in hermaphrodites. Meyer established her first lab at MIT after leaving the MRC, starting with the question of how the nematode specifies its sex. Further analysis of the mechanism underlying dosage compensation produced many key insights into gene regulation. In 1990, Meyer and her husband Tom Cline gave up their tenured positions (she at MIT, he at Princeton) -she accepted a full faculty appointment at the University of California, Berkeley. In 1997, Meyer becomes an HHMI investigator. Her lab identified a gene they named "xol-1" as the master switch for sex determination. Meyer’s group also found that  transcription factors encoded by both the X chromosome and the autosomes battle to control whether "xol-1" is transcriptionally active or inactive. She became a member of ASCB (American association of cell biology) in 1995. She was also elected as a member to AAAS (American academy of Arts and Sciences) in 1995. In 2014, Meyer was elected to the American Philosophical Society. In 2018, Meyer was honored with the E.B. Wilson Medal by American Society for Cell Biology's (ASCB) highest honor for science, for her significant and far-reaching contributions to cell biology over a lifetime in science. Meyer was  also honored with 2018 Thomas Hunt Morgan Medal which is awarded for lifetime achievement in genetics. This honor is given in recognition of her groundbreaking work on chromosome behaviors that govern gene expression, development, and heredity. At the same year, Meyer was elected to the National Academy of Medicine, considered one of the highest honors in health and medicine, “for groundbreaking work on chromosome dynamics that impact gene expression, development and heredity using the nematode as a model organism.