Molecular Biology Commons^™

Calmodulin Like 38 Is Required For Autophagy Of Hypoxia-Induced Cytoplasmic Rna Granules In Arabidopsis Thaliana, Sterling Field

Doctoral Dissertations

In response to the energy crisis resulting from submergence stress and hypoxia, the model plant Arabidopsis thaliana limits non-essential mRNA translation, and accumulates cytosolic stress granules. Stress granules are phase-separated mRNA-protein particles that partition transcripts for various fates: storage, degradation, or return to translation after stress alleviation. Another response by the plant cell to low oxygen stress is the induction of the turnover pathway autophagy. Stress granule regulation by autophagy occurs by a ‘granulophagy’ pathway in yeast and mammalian systems through which parts or whole stress granules are degraded. Whether this occurs in plants has not been investigated.

A connection …

Erecta Family Genes Regulate The Shoot Apical Meristem And Organ Formation, Daniel A. Degennaro

Doctoral Dissertations

Plants are sessile and must adjust their organ growth to their environments. A reservoir of stem cells in the shoot apical meristem (SAM) supplies cells for differentiation into organs. The SAM must balance organ production with stem cell maintenance. The ERECTA family (ERfs) encodes the leucine-rich repeat receptor-like kinases ERECTA (ER), ERECTA-LIKE 1 (ERL1), and ERL2. ERf signaling regulates organ initiation and stem cell maintenance. Results presented in this work include the following:

1) WUSCHEL (WUS) and CLAVATA3 (CLV3) make up a negative feedback loop to maintain SAM size. WUS and CLV3 expression localization is critical for …

Salicylic Acid: A Key Regulator Of Redox Signalling 1 And Plant Immunity, Mohd Saleem, Qazi Fariddudin, Christian Castroverde

Biology Faculty Publications

In plants, the reactive oxygen species (ROS) formed during normal conditions are essential in regulating several processes, like stomatal physiology, pathogen immunity and developmental signaling. However, biotic and abiotic stresses can cause ROS over-accumulation leading to oxidative stress. Therefore, a suitable equilibrium is vital for redox homeostasis in plants, and there have been major advances in this research arena. Salicylic acid (SA) is known as a chief regulator of ROS; however, the underlying mechanisms remain largely unexplored. SA plays an important role in establishing the hypersensitive response (HR) and systemic acquired resistance (SAR). This is underpinned by a robust and …

Mutations In Several Auxin Biosynthesis Genes And Their Effects On Plant Phenotypes In Arabidopsis, Gabriela Hernandez, Lauren Huebner, Bethany Karlin Zolman

Undergraduate Research Symposium

Auxins are important hormones in plants that regulate growth and development. Disruptions in the auxin biosynthesis pathway result in morphological changes in phenotypes in the model plant Arabidopsis thaliana, including differences in root and leaf formation. Mutations in the Tryptophan Aminotransferase of Arabidopsis (TAA1) and YUCCA (YUC4) genes interfere with the plant's ability to synthesize Indole-3-acetic acid (IAA), the primary auxin involved in plant development. IBR1 and IBR3 act in the multistep conversion of indole-3-butyric acid (IBA) to IAA. ILL2, IAR3, and ILR1 hydrolyze IAA-amino acid conjugates into free IAA. The goal of …

Temperature Regulation Of Plant Hormone Signaling During Stress And Development, Christian Castroverde, Damaris Dina

Biology Faculty Publications

Global climate change has broad-ranging impacts on the natural environment and human civilization. Increasing average temperatures along with more frequent heat waves collectively have negative effects on cultivated crops in agricultural sectors and wild species in natural ecosystems. These aberrantly hot temperatures, together with cold stress, represent major abiotic stresses to plants. Molecular and physiological responses to high and low temperatures are intricately linked to the regulation of important plant hormones. In this review, we shall highlight our current understanding of how changing temperatures regulate plant hormone pathways during immunity, stress responses and development. This article will present an overview …

Resistance Screening And Association Mapping For Resistance To The Downy Mildew Pathogen Of Spinach, Dotun Olaoye

Graduate Theses and Dissertations

Spinach is an important cool leafy vegetable cultivated around the world, with large scale production in California and Arizona in the U.S. Spinach is a highly nutritious vegetable beneficial in the human diet. Spinach is affected by a number of biotic stressors. Downy mildew, caused by the oomycete pathogen Peronospora effusa, is a major threat to spinach as it affects the leaf quality and impacts the economic value of spinach. Several efforts have led to the development of resistant genotypes/cultivars to this pathogen. However, few studies have examined the genetics of resistance to the downy mildew pathogen in detail. This …

Lighting The Way: Recent Insights Into The Structure And Regulation Of Phototropin Blue Light Receptors, Jaynee E. Hart, Kevin H. Gardner

Publications and Research

The phototropins (phots) are light-activated kinases that are critical for plant physiology and the many diverse optogenetic tools that they have inspired. Phototropins combine two bluelight- sensing Light–Oxygen–Voltage (LOV) domains (LOV1 and LOV2) and a C-terminal serine/threonine kinase domain, using the LOV domains to control the catalytic activity of the kinase. While much is known about the structure and photochemistry of the light-perceiving LOV domains, particularly in how activation of the LOV2 domain triggers the unfolding of alpha helices that communicate the light signal to the kinase domain, many questions about phot structure and mechanism remain. Recent studies have made …