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Negative Cooperativity Of Uric Acid Binding To The Transcriptional Regulator Hucr From Deinococcus Radiodurans, Steven P. Wilkinson, Anne Grove Jul 2005

Negative Cooperativity Of Uric Acid Binding To The Transcriptional Regulator Hucr From Deinococcus Radiodurans, Steven P. Wilkinson, Anne Grove

Faculty Publications

Members of the MarR family of winged helix transcriptional regulators have been shown to regulate multidrug and oxidative stress response, pathogenesis, and catabolism of aromatic compounds. Many respond to anionic lipophilic compounds in their capacity to bind DNA, and the co-crystal structure of MarR bound to salicylate revealed two ligand-binding pockets, SAL-A and SAL-B. The MarR homolog, HucR, from Deinococcus radiodurans has been shown to repress expression of a predicted uricase, and DNA-binding by HucR is antagonized by uric acid, the substrate of uricase. We provide a biochemical investigation of DNA-binding and uric acid-binding by HucR. Equilibrium analytical ultracentrifugation indicates …

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Effects Of Long-Term Storage On Quality Of Retail-Packaged Pinto Beans, C. M. Larson, A. R. Sloan, Lynn V. Ogden, Oscar A. Pike Jul 2005

Effects Of Long-Term Storage On Quality Of Retail-Packaged Pinto Beans, C. M. Larson, A. R. Sloan, Lynn V. Ogden, Oscar A. Pike

Faculty Publications

There is interest in storing low-moisture foods for long periods of time for uses such as personal preparedness, disaster relief efforts and space travel. Pinto beans in restaurant-sized No. 10 cans are available in the retail market, but work is needed to determine the effects of long-term storage on quality. The objective of this research was to investigate the quality of retail-packaged pinto beans held at ambient temperatures up to 32 years. Fifteen samples of pinto beans packaged in No. 10 cans, which were treated to remove oxygen, were obtained from donors. Samples ranged from <1 to 32 years in age. Prior to cooking, pinto bean samples were soaked in water containing varying levels of baking soda to standardize textural attributes.

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Photochemical Transformations Of Riverine Dissolved Organic Matter: Effects On Estuarine Bacterial Metabolism And Nutrient Demand, Erik M. Smith, Ronald Benner Jul 2005

Photochemical Transformations Of Riverine Dissolved Organic Matter: Effects On Estuarine Bacterial Metabolism And Nutrient Demand, Erik M. Smith, Ronald Benner

Faculty Publications

By experimentally simulating the exposure of terrigenous dissolved organic matter (DOM) to sunlight during the mixing of river water and seawater in an estuary (St. Helena Sound, South Carolina), this study examined how photochemical alterations may affect both the magnitude and fate of DOM utilization by estuarine bacteria. In a series of experiments performed with water samples collected from 3 blackwater rivers draining into an estuary of the South Atlantic Bight (USA), exposure to light resulted in significant decreases in dissolved organic carbon (DOC) concentration and DOM absorption at 350 nm relative to dark controls. When these water samples were …

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Hard-Sphere Radial Distribution Function Again, Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak Jul 2005

Hard-Sphere Radial Distribution Function Again, Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak

Faculty Publications

A theoretically based closed-form analytical equation for the radial distribution function, g(r), of a fluid of hard spheres is presented and used to obtain an accurate analytic representation. The method makes use of an analytic expression for the short- and long-range behaviors of g(r), both obtained from the Percus-Yevick equation, in combination with the thermodynamic consistency constraint. Physical arguments then leave only three parameters in the equation of g(r) that are to be solved numerically, whereas all remaining ones are taken from the analytical solution of the Percus-Yevick equation.

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Enhancement Of Calcium-Dependent Afterpotentials In Oxytocin Neurons Of The Rat Supraoptic Nucleus During Lactation, Ryoichi Teruyama, William E. Armstrong Jul 2005

Enhancement Of Calcium-Dependent Afterpotentials In Oxytocin Neurons Of The Rat Supraoptic Nucleus During Lactation, Ryoichi Teruyama, William E. Armstrong

Faculty Publications

The firing pattern of oxytocin (OT) hormone synthesizing neurons changes dramatically immediately before each milk ejection, when a brief burst of action potentials is discharged. OT neurons possess intrinsic currents that would modulate this burst. Our previous studies showed the amplitude of the Ca2+-dependent afterhyperpolarization (AHP) following spike trains is significantly larger during lactation. In the present study we sought to determine which component of the AHP is enhanced, and whether the enhancement could be related to changes in whole-cell Ca2+ current or the Ca2+ transient in identified OT or vasopressin (VP) neurons during lactation. We confirmed, with whole-cell current-clamp …

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Rotational Legged Locomotion, Damian M. Lyons, Kiran Pamnany Jul 2005

Rotational Legged Locomotion, Damian M. Lyons, Kiran Pamnany

Faculty Publications

In this paper we presented a novel, agile robot mechanism, which we call a rotopod, which combines aspects of wheeled and legged locomotion. A general description of how a tripedal rotopod can be made to step, rotating the mechanism about one leg, and moving the center of the mechanism, is presented. The concept of a gait for this mechanism is defined, and is used to show how extremely agile the mechanism can be. Specific resistance is employed as a way to explore the relative efficiency of this mechanism versus a wheel. Finally, we describe our first prototype rotopod and report …

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Civil-Military Relations In A Civilized State: Panama, Ronald D. Sylvia, Constantine P. Danopoulos Jul 2005

Civil-Military Relations In A Civilized State: Panama, Ronald D. Sylvia, Constantine P. Danopoulos

Faculty Publications

This article traces and analyzes civil-military relations in Panama. After a brief overview of the role of the National Guard in the country politics, the article concentrates on political developments since the 1989 U.S. invasion to overthrow the Noriega regime and the subsequent elimination of the Panamanian military. The study seeks to shed light on political life in an armyless and politically and socially fractionalized country occupying a sensitive strategic location. The concluding part of the study speculates on the possibility that terrorism, domestic security concerns, and regional considerations may prompt Washington and Panamanian leaders to reverse the decision to …

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The 'Abuse Excuse' In Capital Sentencing Trials: Is It Relevant To Responsibility, Punishment, Or Neither?, Paul J. Litton Jul 2005

The 'Abuse Excuse' In Capital Sentencing Trials: Is It Relevant To Responsibility, Punishment, Or Neither?, Paul J. Litton

Faculty Publications

The violent criminal who was a victim of severe childhood abuse frequently appears in the responsibility literature because he presents a difficulty for theorists who maintain the compatibility of causal determinism and our practices of holding persons responsible. The challenge is based on the fact that learning about an offender's horrific childhood mitigates the indignation that many persons feel towards him, possibly indicating that they hold him less than fully responsible. Many capital defendants present evidence of suffering childhood abuse, and many jurors find this evidence to count against imposing death. The most obvious explanation for a response like this …

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V-Atpase Expression During Development Of Artemia Franciscana Embryos: Potential Role For Proton Gradients In Anoxia Signaling, Joseph A. Covi, Steven C. Hand Jul 2005

V-Atpase Expression During Development Of Artemia Franciscana Embryos: Potential Role For Proton Gradients In Anoxia Signaling, Joseph A. Covi, Steven C. Hand

Faculty Publications

Under anoxia, Artemia franciscana embryos downregulate metabolic processes and approach an ametabolic state. Entrance into this quiescent state is accompanied by a profound acidification of the intracellular space, and more than two decades of research now clearly demonstrates that this acidification is critical to metabolic downregulation in anoxic embryos. However, the proximal mechanisms responsible for the pH shift remain largely unidentified. Here, we report evidence demonstrating expression of the V-ATPase in encysted embryos and present an argument for its involvement in the intracellular acidification induced by anoxia. We identified a single B-subunit cDNA sharing the greatest degree of sequence similarity …

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V-Atpase Inhibition Prevents Recovery From Anoxia In Artemia Franciscana Embryos: Quiescence Signaling Through Dissipation Of Proton Gradients, Joseph A. Covi, W. Dale Treleaven, Steven C. Hand Jul 2005

V-Atpase Inhibition Prevents Recovery From Anoxia In Artemia Franciscana Embryos: Quiescence Signaling Through Dissipation Of Proton Gradients, Joseph A. Covi, W. Dale Treleaven, Steven C. Hand

Faculty Publications

The metabolic downregulation critical for long-term survival of Artemia franciscana embryos under anoxia is mediated, in part, by a progressive intracellular acidification. However, very little is known about the mechanisms responsible for the pH transitions associated with exposure to, and recovery from, oxygen deprivation. In the present study, we demonstrate with 31P-NMR that incubation of intact embryos with the V-ATPase inhibitor bafilomycin A1 severely limits intracellular alkalinization during recovery from anoxia without affecting the restoration of cellular nucleotide triphosphate levels. Based on these data, it appears that oxidative phosphorylation and ATP resynthesis can only account for the first 0.3 pH …

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The Regulation Of Fatty Acid Synthase By Stat5a, Jessica C. Hogan, Jacqueline M. Stephens Jul 2005

The Regulation Of Fatty Acid Synthase By Stat5a, Jessica C. Hogan, Jacqueline M. Stephens

Faculty Publications

Growth hormone (GH) diminishes adipose tissue mass in vivo and decreases expression and activity of fatty acid synthase (FAS) in adipocytes. GH and prolactin (PRL) are potent activators of STAT5 and exert adipogenic and antiadipogenic effects in adipocytes. In this study, we demonstrate that GH and PRL decrease the mRNA and protein levels of FAS in 3T3-L1 adipocytes. We present evidence that indicates that FAS is repressed at the level of transcription. In addition, PRL responsiveness was shown to exist between -1,594 and -700 of the rat FAS promoter. Moreover, responsiveness to PRL was abolished with mutation of a site …

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Ethnicity, Education, And Blood Pressure In Cuba, Pedro Ordunez, Jose Luis Bernal Munoz, Alfredo Espinosa-Brito, Luis Carlos Silva, Richard S. Cooper Jul 2005

Ethnicity, Education, And Blood Pressure In Cuba, Pedro Ordunez, Jose Luis Bernal Munoz, Alfredo Espinosa-Brito, Luis Carlos Silva, Richard S. Cooper

Faculty Publications

The causes of variation in hypertension risk by ethnicity and educational level are not well understood. To gain further insight into this issue in a nonindustrialized country, a population-based sample of 1,667 persons aged 15-74 years was recruited in Cienfuegos, Cuba. In this 2001-2002 study, interviewers classified 29% of participants as Black or mulatto and 71% as White. Educational attainment was stratified at the median number of school years. Compared with White women, non-White women had higher blood pressures (3.0/1.7, systolic blood pressure/ diastolic blood pressure) and a higher prevalence of hypertension (24%, 95% confidence interval: 20, 28 vs. 15%, …

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Beyond Women And Economics: Rereading "Women's Work", Drucilla K. Barker Jul 2005

Beyond Women And Economics: Rereading "Women's Work", Drucilla K. Barker

Faculty Publications

No abstract provided.

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Calibration And Evaluation Of An Objective Measure Of Physical Activity In Preschool Children, John R. Sirard, Stewart G. Trost, Karin A. Pfeiffer, Marsha Dowda, Russell R. Pate Jul 2005

Calibration And Evaluation Of An Objective Measure Of Physical Activity In Preschool Children, John R. Sirard, Stewart G. Trost, Karin A. Pfeiffer, Marsha Dowda, Russell R. Pate

Faculty Publications

Background: The purposes of this study were 1) to establish accelerometer count cutoffs to categorize activity intensity of 3 to 5-y old-children and 2) to evaluate the accelerometer as a measure of children's physical activity in preschool settings. Methods: While wearing an ActiGraph accelerometer, 16 preschool children performed five, 3-min structured activities. Receiver Operating Characteristics (ROC) curve analyses identified count cutoffs for four physical activity intensities. In 9 preschools, 281 children wore an ActiGraph during observations performed by three trained observers (interobserver reliability = 0.91 to 0.98). Results: Separate count cutoffs for 3, 4, and 5-y olds were established. Sensitivity …

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Giftedness, Disadvantage, And Law, Cynthia V. Ward Jul 2005

Giftedness, Disadvantage, And Law, Cynthia V. Ward

Faculty Publications

No abstract provided.

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Effectively Using Recurrently-Connected Spiking Neural Networks, Eric Goodman, Dan A. Ventura Jul 2005

Effectively Using Recurrently-Connected Spiking Neural Networks, Eric Goodman, Dan A. Ventura

Faculty Publications

Recurrently-connected spiking neural networks are difficult to use and understand because of the complex nonlinear dynamics of the system. Through empirical studies of spiking networks, we deduce several principles which are critical to success. Network parameters such as synaptic time delays and time constants and the connection probabilities can be adjusted to have a significant impact on accuracy. We show how to adjust these parameters to fit the type of problem.

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Time Invariance And Liquid State Machines, Eric Goodman, Dan A. Ventura Jul 2005

Time Invariance And Liquid State Machines, Eric Goodman, Dan A. Ventura

Faculty Publications

Time invariant recognition of spatiotemporal patterns is a common task of signal processing. Liquid state machines (LSMs) are a paradigm which robustly handle this type of classification. Using an artificial dataset with target pattern lengths ranging from 0.1 to 1.0 seconds, we train an LSM to find the start of the pattern with a mean absolute error of 0.18 seconds. Also, LSMs can be trained to identify spoken digits, 1-9, with an accuracy of 97.6%, even with scaling by factors ranging from 0.5 to 1.5.

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Early-Stage Folding In Proteins (In Silico) Sequence-To-Structure Relation, Michal Brylinski, Leszek Konieczny, Patryk Czerwonko, Wiktor Jurkowski, Irena Roterman Jun 2005

Early-Stage Folding In Proteins (In Silico) Sequence-To-Structure Relation, Michal Brylinski, Leszek Konieczny, Patryk Czerwonko, Wiktor Jurkowski, Irena Roterman

Faculty Publications

A sequence-to-structure library has been created based on the complete PDB database. The tetrapeptide was selected as a unit representing a well-defined structural motif. Seven structural forms were introduced for structure classification. The early-stage folding conformations were used as the objects for structure analysis and classification. The degree of determinability was estimated for the sequence-to-structure and structure-to-sequence relations. Probability calculus and informational entropy were applied for quantitative estimation of the mutual relation between them. The structural motifs representing different forms of loops and bends were found to favor particular sequences in structure-to-sequence analysis. © 2005 Hindawi Publishing Corporation.

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Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore Phd, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir Jun 2005

Ecotypic Variation In Phosphorus Acquisition Mechanisms Within Marine Picocyanobacteria, Lisa Moore Phd, M. Ostrowski, D. J. Scanlan, K. Feren, T. Sweetsir

Faculty Publications

Prochlorococcus and Synechococcus are major prokaryotic primary producers in the oligotrophic oceans that may be affected by the climate-related increases in nitrogen fixation and subsequent phosphorus (P) limitation in some parts of the oceans. Evidence that Prochlorococcus populations in the North Pacific subtropical gyre (NPSG) have increased over the past decades, possibly due to having a competitive advantage under conditions of P limitation, suggests aspects of their Pphysiology that are important for dictating their in situ success. Here, we compared the physiology of P acquisition and response to P stress (indicated by alkaline phosphatase activity, APA) among isolates of Prochlorococcus …

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Integration Of Computer-Based Electronics Laboratory In A Control Systems Course, Julio Garcia, Patricia Backer Jun 2005

Integration Of Computer-Based Electronics Laboratory In A Control Systems Course, Julio Garcia, Patricia Backer

Faculty Publications

The goal of this project is to adapt the work of other researchers to improve the delivery of electronics lecture and laboratory content in the Electronics & Computer Technology (ECT) area of the BS in Industrial Technology at San Jose State University. There are several other demographic factors that serve to make the delivery of instruction challenging for the department. Approximately 70% of ECT students work at least 30 hours a week. SJSU also has a diverse student population with 62% of all undergraduates identified as having non-White ethnicity. A higher percentage (69%) of the undergraduate students in the BSIT …

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Effects Of Leukemia Inhibitory Factor On 3t3-L1 Adipocytes, Jessica C. Hogan, Jacqueline M. Stephens Jun 2005

Effects Of Leukemia Inhibitory Factor On 3t3-L1 Adipocytes, Jessica C. Hogan, Jacqueline M. Stephens

Faculty Publications

Leukemia inhibitory factor (LIF) is a member of the gp130 cytokine family and signals through the receptor complex of gp130 and the LIF receptor (LIFR) to activate the JAK/STAT signaling cascade. Since LIF activates STATs 1 and 3 in adipocytes, we examined the effects of LIF on 3T3-L1 adipocytes. Our studies clearly demonstrate that LIF treatment had minimal effects on adipocyte differentiation as judged by marker gene expression, but did inhibit triacylglyceride (TAG) accumulation during adipogenesis. Acute treatment with LIF resulted in increased expression of suppressors of cytokine signaling-3 (SOCS3) and CCAAT/enhancer-binding protein-δ (C/EBPδ) mRNA in 3T3-L1 adipocytes. Moreover, the …

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Boron Neutron Capture Therapy Of Cancer: Current Status And Future Prospects, Rolf F. Barth, Jeffrey A. Coderre, M. Graça H. Vicente, Thomas E. Blue Jun 2005

Boron Neutron Capture Therapy Of Cancer: Current Status And Future Prospects, Rolf F. Barth, Jeffrey A. Coderre, M. Graça H. Vicente, Thomas E. Blue

Faculty Publications

Background: Boron neutron capture therapy (BNCT) is based on the nuclear reaction that occurs when boron-10 is irradiated with low-energy thermal neutrons to yield high linear energy transfer α particles and recoiling lithium-7 nuclei. Clinical interest in BNCT has focused primarily on the treatment of high-grade gliomas and either cutaneous primaries or cerebral metastases of melanoma, most recently, head and neck and liver cancer. Neutron sources for BNCT currently are limited to nuclear reactors and these are available in the United States, Japan, several European countries, and Argentina. Accelerators also can be used to produce epithermal neutrons and these are …

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Subzero Water Permeability Parameters And Optimal Freezing Rates For Sperm Cells Of The Southern Platyfish, Xiphophorus Maculatus, D. Pinisetty, C. Huang, Q. Dong, T. R. Tiersch, R. V. Devireddy Jun 2005

Subzero Water Permeability Parameters And Optimal Freezing Rates For Sperm Cells Of The Southern Platyfish, Xiphophorus Maculatus, D. Pinisetty, C. Huang, Q. Dong, T. R. Tiersch, R. V. Devireddy

Faculty Publications

This study reports the subzero water transport characteristics (and empirically determined optimal rates for freezing) of sperm cells of live-bearing fishes of the genus Xiphophorus, specifically those of the southern platyfish Xiphophorus maculatus. These fishes are valuable models for biomedical research and are commercially raised as ornamental fish for use in aquariums. Water transport during freezing of X. maculatus sperm cell suspensions was obtained using a shape-independent differential scanning calorimeter technique in the presence of extracellular ice at a cooling rate of 20°C/min in three different media: (1) Hanks' balanced salt solution (HBSS) without cryoprotective agents (CPAs); (2) HBSS with …

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An Evolutionary Algorithm To Generate Hyper-Ellipsoid Detectors For Negative Selection, Joseph M. Shapiro, Gary B. Lamont, Gilbert L. Peterson Jun 2005

An Evolutionary Algorithm To Generate Hyper-Ellipsoid Detectors For Negative Selection, Joseph M. Shapiro, Gary B. Lamont, Gilbert L. Peterson

Faculty Publications

This paper introduces hyper-ellipsoids as an improvement to hyper-spheres as intrusion detectors in a negative selection problem within an artificial immune system. Since hyper-spheres are a specialization of hyper-ellipsoids, hyper-ellipsoids retain the benefits of hyper-spheres. However, hyper-ellipsoids are much more flexible, mostly in that they can be stretched and reoriented. The viability of using hyper-ellipsoids is established using several pedagogical problems. We conjecture that fewer hyper-ellipsoids than hyper-spheres are needed to achieve similar coverage of nonself space in a negative selection problem. Experimentation validates this conjecture. In pedagogical benchmark problems, the number of hyper-ellipsoids to achieve good results is significantly …

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The Role Of Religion In The Transition To Adulthood For Young Emerging Adults, Carolyn Mcnamara Barry, Larry J. Nelson Jun 2005

The Role Of Religion In The Transition To Adulthood For Young Emerging Adults, Carolyn Mcnamara Barry, Larry J. Nelson

Faculty Publications

Recent research has highlighted the role of culture in emerging adulthood (age between 18 and 25 years). However, most studies have examined majority cultures (e.g., China) as well as subcultures (e.g., American ethnic minorities). Thus, work on other aspects of culture such as religion is needed given the emerging evidence that it may have an impact on development. This study explored the role of religious culture in the emerging adulthood of college students. Participants were 445 undergraduates (ages 18–20 years) from institutions that were Catholic (31 males, 89 females), Mormon (48 males, 200 females), and public (21 males, 56 females). …

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Religion And Bio-Psycho-Social Health: A Review And Conceptual Model, Loren Marks Jun 2005

Religion And Bio-Psycho-Social Health: A Review And Conceptual Model, Loren Marks

Faculty Publications

This paper presents a research-based conceptual model respectively linking three dimensions of religious experience (religious practices, spiritual beliefs, and faith community) with three dimensions of health (biological, psychological, and social). The model is used as a framework to highlight findings in the religion-health knowledge base and to provide a broad survey of this domain of inquiry. Considerations for future research on religion and health are addressed.

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Nrg1, A Cc-Nb-Lrr Protein, Together With N, A Tir-Nb-Lrr Protein, Mediates Resistance Against Tobacco Mosaic Virus, Jack R. Peart, Pere Mestre, Rui Lu, Isabelle Malcuit, David C. Baulcombe May 2005

Nrg1, A Cc-Nb-Lrr Protein, Together With N, A Tir-Nb-Lrr Protein, Mediates Resistance Against Tobacco Mosaic Virus, Jack R. Peart, Pere Mestre, Rui Lu, Isabelle Malcuit, David C. Baulcombe

Faculty Publications

In animals and plants, innate immunity is regulated by nucleotide binding domain and leucine-rich repeat (NB-LRR) proteins that mediate pathogen recognition and that activate host-cell defense responses [1, 2]. Plant NB-LRR proteins, referred to as R proteins, have amino-terminal domains that contain a coiled coil (CC) or that share similarity with animal Toll and interleukin 1 receptors (TIR) [3]. To investigate R protein function, we are using the TIR-NB-LRR protein N that mediates resistance against tobacco mosaic virus (TMV) [4] through recognition of the TMV p50 protein. Here, we describe N requirement gene 1 (NRG1), a novel N-resistance component that …

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Female Breast Cancer Incidence And Survival In Utah According To Religious Preference, 1985-1999, Ray M. Merrill, Jeffrey A. Folsom May 2005

Female Breast Cancer Incidence And Survival In Utah According To Religious Preference, 1985-1999, Ray M. Merrill, Jeffrey A. Folsom

Faculty Publications

Female breast cancer incidence rates in Utah are among the lowest in the U.S. The influence of the Church of Jesus Christ of Latter-day Saint (LDS or Mormon) religion on these rates, as well as on disease-specific survival, will be explored for individuals diagnosed with breast cancer in Utah from 1985 through 1999. Methods: Population-based records for incident female breast cancer patients were linked with membership records from the LDS Church to determine religious affiliation and, for LDS Church members, level of religiosity. Incidence rates were age-adjusted to the 2000 U.S. standard population using the direct method. Cox proportional hazards …

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Alu Retrotransposition-Mediated Deletion, Pauline A. Callinan, Jianxin Wang, Scott W. Herke, Randall K. Garber, Ping Liang, Mark A. Batzer May 2005

Alu Retrotransposition-Mediated Deletion, Pauline A. Callinan, Jianxin Wang, Scott W. Herke, Randall K. Garber, Ping Liang, Mark A. Batzer

Faculty Publications

Alu repeats contribute to genomic instability in primates via insertional and recombinational mutagenesis. Here, we report an analysis of Alu element-induced genomic instability through a novel mechanism termed retrotransposition-mediated deletion, and assess its impact on the integrity of primate genomes. For human and chimpanzee genomes, we find evidence of 33 retrotransposition-mediated deletion events that have eliminated approximately 9000 nucleotides of genomic DNA. Our data suggest that, during the course of primate evolution, Alu retrotransposition may have contributed to over 3000 deletion events, eliminating approximately 900 kb of DNA in the process. Potential mechanisms for the creation of Alu retrotransposition-mediated deletions …

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Phytochrome Evolution In Green And Nongreen Plants, Sarah Mathews May 2005

Phytochrome Evolution In Green And Nongreen Plants, Sarah Mathews

Faculty Publications

Photoreceptors are critical molecules that function at the interface between organism and environment. Plants use specific light signals to determine their place in time and space, allowing them to synchronize their growth, metabolism, and development to the environments in which they occur. Thus, innovation in light sensing mechanisms is expected to coincide with adaptation and diversification. Three studies involving the well-characterized phytochrome photoreceptor system in plants indicate that much work is yet needed to test this expectation. In early diverging dowering plants, episodic positive selection influenced the evolution of phytochrome A, but little of the functional data needed to link …

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