dictyNews Electronic Edition Volume 28, number 17 June 16, 2007 Please submit abstracts of your papers as soon as they have been accepted for publication by sending them to dicty@northwestern.edu or by using the form at http://dictybase.org/db/cgi-bin/dictyBase/abstract_submit. Back issues of dictyNews, the Dicty Reference database and other useful information is available at dictyBase - http://dictybase.org. ========= Abstracts ========= DRpp20 and DRpp40: two protein subunits involved in Dictyostelium discoideum ribonuclease P holoenzyme assembly Dimitra Kalavrizioti, Anastassios Vourekas and Denis Drainas Department of Biochemistry, School of Medicine, University of Patras, Greece. Accepted for publication, Gene Abstract Ribonuclease P is an essential enzyme that matures the 5´ ends of all primary tRNA transcripts. RNase P enzymes contain a similar in size RNA subunit which is absolutely required for catalysis. The holoenzyme from Dictyostelium discoideum possesses an essential for activity RNA subunit but the exact protein composition is still under investigation. Bioinformatic analysis of D. discoideum sequencing data returned seven ORFs homologous to previously characterized RNase P protein subunits from human. In the present study, DRpp20 and DRpp40 were cloned and characterized. These proteins apart from the noted similarity, possess idiosyncratic regions. Immunobiochemichal analysis presented herein indicates their direct involvement in the formation of the ribonucleoprotein complex of D. discoideum RNase P holoenzyme. Submitted by: Denis Drainas [Drainas@med.upatras.gr] -------------------------------------------------------------------------------- The Cold War of the Social Amoebae Gad Shaulsky and Richard H. Kessin Department of Molecular and Human Genetics Baylor College of Medicine, One Baylor Plaza, Houston, Texas, 77030. USA and Department of Pathology and Cell Biology, Columbia University, 630 West 168th St. New York, New York, 10027, USA Accepted, Current Biology Abstract: When confronted with starvation, the amoebae of Dictyostelium discoideum initiate a developmental process that begins with cell aggregation and ends with a ball of spores supported on a stalk. Spores live and stalk cells die. Because the organism is created by cell aggregation and not by growth and division of a single cell, genetically diverse amoebae may enter an aggregate and if one lineage has a capacity to avoid the stalk cell fate, it may have a selective advantage. Such cheater mutants have been found among wild isolates and created in laboratory strains. The mutants raise a number of questions ­ how did such a cooperative system evolve in the face of cheating? What is the basis of self recognition? What genes are involved? How is cheating constrained? This review summarizes the results of studies on the social behavior of Dictyostelium and its relatives, including the familiar asexual developmental cycle and the less known, but puzzling sexual cycle. Submitted by: Rich Kessin [rhk2@columbia.edu] ============================================================== [End dictyNews, volume 28, number 17]