GRAVITATIONAL AND SPACE BIOLOGY BULLETIN Volume 13, Number 2 June 2000 Publication of the American Society for Gravitational and Space Biology ISSN 1089-988X ASGSB GOVERNING BOARD EDITOR-IN-CHIEF Jay C. Buckey Marian L. Lewis Mary E. Musgrave President President-Elect University of Massachusetts Dartmouth Medical School University of Alabama Amherst, MA Hanover, NH Huntsville,AL Kenneth A. Souza Norman G. Lewis SCIENCE EDITORS Secretary Treasurer Immediate Past President Washington State University NASA Ames Research Center Karl H. Hasenstein Pullman, WA Moffett Field, CA University of Southwestern Louisiana Lafayette, LA Patricia Russell Janet Braam Mary E. Musgrave Executive Director Rice University University of Massachusetts USRA Houston, TX Amherst, MA Washington, DC Thomas W. Dreschel Charles Fuller Dynamac Corporation University of California PUBLISHING EDITOR Kennedy Space Center, FL Davis, CA Mary E. Musgrave University of Massachusetts Karl H. Hasenstein John Z. Kiss Amherst, MA University of Southwestern Louisiana Miami University Lafayette, LA Oxford, OH ASSISTANT EDITOR Bonnie J. McClain Danny A. Riley Kathleen Chick Colorado State University Medical College of Wisconsin University of Massachusetts Fort Collins, CO Milwaukee, WI Amherst MA Tom K. Scott Michael Wiederhold University of North Carolina University of Texas Health Science Center Chapel Hill, NC San Antonio, TX CORPORATE MEMBERS ASSOCIATE CORPORATE MEMBERS Boeing Company Lockheed-Martin, Inc. SHOT, Inc. Mains Associates, Inc. ORBITEC, Inc. Seal Beach, CA Moffett Field, CA Floyd Knobs, IN Berkeley, CA Madison, WI GENERAL INFORMATION Gravitational and Space Biology Bulletin (ISSN 1089-988X) is a journal devoted to research in gravitational and space biology. It is published by the American Society for Gravitational and Space Biology, a non-profit organization whose members share a common goal of furthering the understanding of the biological effects of gravity and the use of the unique environment of spaceflight for biological research. The Bulletin is overseen by a steering committee consisting of the Publications Committee, the Bulletin Editor, the President, and the Secretary- Treasurer of the ASGSB. This issue of Gravitational and Space Biology Bulletin was printed at Common Wealth Printing Co., Inc., Hadley, Massachusetts.. The American Society for Gravitational and Space Biology was created in 1984 to provide an avenue for scientists interested in gravitational and space biology to share information and join together to speak with a united voice in support of this field of science. The biological effects of gravity have been acknowledged since Galileo's time, but only in this century has gravitational biology begun to attract attention. With the birth of the space age, the opportunity for experimentation over the full spectrum of gravity finally became a reality, and a new environment and research tool became available to probe biological phenomena and expand scientific knowledge. Space and spaceflight introduced new questions about space radiation and the physiological and psychological effects of the artificial environment of spacecraft. The objectives of ASGSB are: · To promote research, education, training, and development in the areas of gravitational and space biology and to apply the knowledge gained to a better understanding of the effect of gravity and space environmental factors on the flora and fauna of Earth. · To disseminate information on gravitational and space biology research and the application of this research to the solution of terrestrial and space biological problems. · To provide a forum for communication among professionals in academia, government, business, and other segments of society involved in gravitational and space biological research and application. · To promote the study of concepts and the implementation of programs that can achieve these ends and further the advancement and welfare of humankind. A Collaborative Production: This issue of the Gravitational and Space Biology Bulletin was produced through a collaboration with the Professional Writing and Technical Communication Program at the University of Massachusetts Amherst. Under the direction of Dr. John Nelson, the PWTC Program has trained students for a variety of professions that demand excellent technical writing and editing skills. Since its inception in 1990, the program has placed nearly 100% of its graduates. The American Society for Gravitational and Space Biology is pleased to sponsor an editorial fellowship for students in the PWTC program at the University of Massachusetts, and gratefully acknowledges the contributions of its students and directors to the production of our journal. MEMBERSHIP: The American Society for Gravitational and Space Biology welcomes individual, organizational, and corporate members in all of the basic and applied fields of the space and gravitational life sciences. Members are active in the fields of space medicine, plant and animal gravitational physiology, cell and developmental biology, biophysics, and space hardware and life support system development. Membership is open to nationals of all countries. Members must have education or research or applied experience in areas related to the Society's purposes: i.e., Doctorate, Masters with 2 years experience, Bachelors with 4 years experience (student members must be actively enrolled in an academic curriculum leading toward a career related to the Society's purposes), or special appointment by the Board of Directors. Membership applications may be obtained by writing the American Society for Gravitational and Space Biology, P.O. Box 12247, Rosslyn, VA 22219. Gravitational and Space Biology Bulletin is sent to all members of the American Society for Gravitational and Space Biology. Requests for copies, information about subscriptions and membership, changes of address, questions on permission to reproduce parts of this volume, and other correspondence should be sent to the American Society for Gravitational and Space Biology, P.O. Box 12247, Rosslyn, VA 22219. Copyright © 2000 by the American Society for Gravitational and Space Biology 2 Gravitational and Space Biology Bulletin 13(2), June 2000 TABLE OF CONTENTS LIFE IN EXTREME ENVIRONMENTS Extremophiles in Astrobiology: Per Ardua ad Astra. Jonathan D. Trent .............................................................. 5 Metazoans in Extreme Environments: Adaptations of Hydrothermal Vent and Hydrocarbon Seep Fauna. Erin R. McMullin, Derk C. Bergquist and Charles R. Fisher ...........................................................................13 Life at Body Temperatures below 0°C: The Physiology and Biochemistry of Antarctic Fishes. Bruce D. Sidell ......................................................................................................................................................25 Life in Extreme Environments: How Will Humans Perform on Mars? Dava J. Newman........................................35 Bold Endeavors: Behavioral Lessons from Polar and Space Exploration. Jack W. Stuster .....................................49 CELLULAR CYBERNETICS: THE ROLE OF THE CYTOSKELETON Cortical Microtubules Form a Dynamic Mechanism That Helps Regulate the Direction of Plant Growth. Clive W. Lloyd, Regina Himmelspach, Peter Nick and Carol Wymer ...................................................................59 Mechanical Forces in Plant Growth and Development. Deborah D. Fisher and Richard J. Cyr .............................67 The Actin Cytoskeleton May Control the Polar Distribution of an Auxin Transport Protein. Gloria K. Muday, Shiquan Hu and Shari R. Brady ...........................................................................................75 Control of Development and Motility in the Spermatozoids of Lower Plants. Stephen M. Wolniak, Vincent P. Klink, Peter E. Hart and Chia-Wei Tsai..................................................................................................85 Columella Cells Revisited: Novel Structures, Novel Properties, and a Novel Gravisensing Model. L. Andrew Staehelin, Hui Qiong Zheng, Thomas L. Yoder, Jeffrey D. Smith and Paul Todd..................................95 Gravitational and Space Biology Bulletin 13(2), June 2000 3 4 Gravitational and Space Biology Bulletin 13(2), June 2000 Extremophiles in Astrobiology: Per Ardua ad Astra Jonathan D. Trent Astrobiology Technology Branch, NASA Ames Research Center, Moffett Field CA ABSTRACT · terrestrial and submarine hot springs, where As we consider the possibilities of finding life on other thermophiles grow at temperatures above 100°C planets, it behooves us to evaluate what we know about the limits (the current highest temperature observed is for life on planet Earth. In our continued exploration of Earth, we 113°C) (Blöchl et al., 1997). are finding microbes in a variety of unexpected habitats. In Microbes have also ingeniously adapted to extremes of radiation, geothermal hot springs, we have discovered organisms thriving at toxin concentrations, low nutrients (starvation), water activity, temperatures near the boiling point of water and at pH values longevity, and other seemingly bizarre conditions (Kushner, 1981; down to 0.5; in the deepest parts of the oceans, those that grow Scheie, 1970). optimally at pressures above 1000 bars and die at pressures below Here the focus will not be on cataloging the esoteric extremes 500 bars; and at the poles, those that grow below the freezing point to which life has adapted, but