Newswise — BETHESDA, MD—December 4, 2012 – Listed below are the selected highlights for the December 2012 issue of the Genetics Society of America’s journal, GENETICS. The December issue is available online at www.genetics.org/content/current. Please credit GENETICS, Vol. 192, December 2012, Copyright © 2012.
Please feel free to forward to colleagues who may be interested in these articles.
Genetic variation in Saccharomyces cerevisiae: Circuit diversification in a signal transduction network, pp. 1523–1532Brian L. Chin, Owen Ryan, Fran Lewitter, Charles Boone, and Gerald R. FinkThe plummeting cost of genome sequencing has revealed increasing amounts of genetic variation within a species. How much of that variation affects function, and how might it help us understand evolution? The authors addressed these questions by looking at how cell adhesion is controlled in two closely related yeast strains. Despite their similar genomic sequences, these two strains use different sets of genes to regulate adhesion. A signal transduction pathway has been rewired, partly because of polymorphisms in a transcription factor.
Gene functional trade-offs and the evolution of pleiotropy, pp. 1389–1409Frédéric Guillaume and Sarah P. OttoPleiotropy—the property of genes affecting multiple features of an organism—is often considered to be an unavoidable by-product of a gene’s evolutionary history. These authors explored how the pleiotropic degree of a gene may evolve, providing clues to why pleiotropy varies among genes. They found two common outcomes of the evolution of multifunctional genes: increased pleiotropy of genes more highly expressed, and specialization of all genes on the trait most important to fitness.
Receptors and other signaling proteins required for serotonin control of locomotion in Caenorhabditis elegans, pp. 1359–1371Güliz Gürel, Megan A. Gustafson, Judy S. Pepper, H. Robert Horvitz, and Michael R. KoelleThis article offers insight into the mechanism of signaling by serotonin, a neurotransmitter involved in mood disorders in humans. The authors carried out screens for C. elegans mutants that fail to respond properly to this neurotransmitter, which worms use to control locomotion. They identified mutations in more than eight genes required for serotonin signaling. Two encode serotonin receptors, while the others encode proteins that in some cases are implicated for the first time in serotonin signaling by this work. There are similar human proteins that may mediate serotonin signaling in our brains. The two C. elegans serotonin receptors appear to act in parallel in different cells to coordinate behavioral responses to serotonin.
Long-term and short-term evolutionary impacts of transposable elements on Drosophila, pp. 1411–1432Yuh Chwen G. Lee and Charles H. LangleyTransposable elements are ubiquitous genomic parasites. Even though they are primarily vertically inherited as part of the genome, their interactions with the host are often likened to the coevolution of host genes and nongenomic, horizontally transferred pathogens. Here Lee and Langley show that genes involved in the interaction with transposable elements indeed show strong signals of positive selection similar to those of immunity genes in Drosophila, but with a fundamentally different mechanism from that of host-pathogen coevolution.
Unusual and typical features of a novel restorer-of-fertility gene of sugar beet (Beta vulgaris L.), pp. 1347–1358Hiroaki Matsuhira, Hiroyo Kagami, Masayuki Kurata, Kazuyoshi Kitazaki, Muneyuki Matsunaga, Yuko Hamaguchi, Eiki Hagihara, Minoru Ueda, Michiyo Harada, Aki Muramatsu, Rika Yui-Kurino, Kazunori Taguchi, Hideto Tamagake, Tetsuo Mikami, and Tomohiko KuboPlant pollen production is often impaired by incompatibility between the mitochondria and nucleus. A nuclear gene termed Rf can cancel this cytoplasmic male sterility. These authors report that sugar beet Rf encodes a metalloprotease-like gene, in contrast to other Rfs which encode proteins supposed to bind RNA. Interestingly, the sugar beet Rf locus exhibits the gene clustering often seen in plant Rf loci, suggesting a common evolutionary mechanism regardless of the Rf gene products.
CloudMap: A cloud-based pipeline for analysis of mutant genome sequences, pp. 1249–1269Gregory Minevich, Danny S. Park, Daniel Blankenberg, Richard J. Poole, and Oliver HobertThis article describes a cloud-based data-analysis pipeline that greatly simplifies analysis of mutant genome sequences. Available on the Galaxy platform, CloudMap requires no software installation and is modular, and thus able to accommodate new software tools as they become available. CloudMap uses a series of predefined workflows, allowing users to arrive at a mapping region and a list of variants with a few clicks.
Epigenetic regulation of axonal growth of Drosophila pacemaker cells by histone acetyltransferase Tip60 controls sleep, pp. 1327–1345Sheila K. Pirooznia, Kellie Chiu, May T. Chan, John E. Zimmerman, and Felice ElefantThis article provides insight into sleep disturbances caused by neurodegenerative diseases. In Drosophila, misregulation of the histone acetyltransferase Tip60 causes sleep disturbances similar to those seen in Alzheimer’s disease patients, with nighttime sleep disruption and daytime sleepiness. These authors show that Tip60 interacts with amyloid precursor protein (APP) to mediate axonal growth of Drosophila pacemaker cells and their production of a neuropeptide that stabilizes sleep–wake cycles. Remarkably, excess Tip60 rescues sleep disruption caused by APP-induced neurodegenerative conditions.
Genetic basis of a violation of Dollo’s law: Re-evolution of rotating sex combs in Drosophila bipectinata, pp. 1465–1475Thaddeus Seher, Chen Siang Ng, Sarah Signor, Ondrej Podlaha, Olga Barmina, and Artyom Kopp“Dollo’s law” posits that complex traits, once lost during evolution, cannot be regained. However, phylogenetic analyses reveal occasional violations of this law. This article describes the genetic basis of one such reversal. Rotated sex combs were lost and subsequently regained in the ananassae species subgroup of Drosophila. This reversal is largely associated with one chromosomal inversion that covers 5% of the genome, suggesting that rotating sex combs may have re-evolved though changes in relatively few genes.
A comprehensive genetic approach for improving prediction of skin cancer risk in humans, pp. 1493–1502Ana I. Vazquez, Gustavo de los Campos, Yann C. Klimentidis, Guilherme J. M. Rosa, Daniel Gianola, Nengjun Yi, and David B. AllisonPredicting complex traits in humans is difficult because most of the genetic variance remains unaccounted for and many small-effect genes are usually involved. These investigators developed several models for predicting skin cancer risk. Prediction improved significantly when genetic parameters such as family history and geographical ancestry were included, especially when thousands of markers across the genome were considered. These methods could be extended to prediction of other diseases.
This Month's Perspectives
Mammalian developmental genetics in the twentieth century, pp. 1151–1163Karen ArtztThis Perspectives reviews the breathtaking history of mammalian genetics in the past century from a mouse developmental geneticist’s point of view. The dizzying speed of progress is illustrated with selected examples of genetic enigmas now solved and includes a retrospective discussion of the T/t complex. It is a story of how hypothesis-driven research got us where we are. These stories should be of interest especially to younger geneticists.
ABOUT GENETICS: Since 1916, GENETICS (http://www.genetics.org/) has covered high quality, original research on a range of topics bearing on inheritance, including population and evolutionary genetics, complex traits, developmental and behavioral genetics, cellular genetics, gene expression, genome integrity and transmission, and genome and systems biology. GENETICS, a peer-reviewed, peer-edited journal of the Genetics Society of America is one of the world's most cited journals in genetics and heredity.
ABOUT GSA: Founded in 1931, the Genetics Society of America (GSA) is the professional membership organization for scientific researchers, educators, bioengineers, bioinformaticians and others interested in the field of genetics. Its nearly 5,000 members work to advance knowledge in the basic mechanisms of inheritance, from the molecular to the population level. GSA is dedicated to promoting research in genetics and to facilitating communication among geneticists worldwide through its conferences, including the biennial conference on Model Organisms to Human Biology, an interdisciplinary meeting on current and cutting edge topics in genetics research, as well as annual and biennial meetings that focus on the genetics of particular organisms, including C. elegans, Drosophila, fungi, mice, yeast, and zebrafish. GSA publishes GENETICS, a leading journal in the field and an online, open-access journal, G3: Genes|Genomes|Genetics. For more information about GSA, please visit www.genetics-gsa.org. Also follow GSA on Facebook at facebook.com/GeneticsGSA and on Twitter @GeneticsGSA.