Life Sciences 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 …

Identification And Functional Characterization Of Plant Small Secreted Proteins During Arbuscular Mycorrhizal Symbiosis, Xiaoli Hu

Doctoral Dissertations

Plant small secreted proteins (SSPs) are sequences of 50 – 250 amino acids in size which are transported out of cells to fulfill multiple functions related to plant growth and development and response to various stresses. With the development of more accurate and affordable genome sequencing technology, an increasing number of SSPs have been predicted using diverse computational tools based on machine learning. Although experimentally validated plant SSPs are still limited, some studies have reported that plant SSPs can be induced and involved in mutualistic relationships between plants and microbes. In Chapter I, known SSPs and their functions in various …

Epigenetic Mechanisms Governing Plant Growth, Development, And Responses To Nematode Parasitism, Meredith M. Bennett

Doctoral Dissertations

Epigenetic mechanisms, including histone and DNA methylation and microRNAs, play key roles in mediating transcriptional changes during plant development and stress responses. However, how these interconnected epigenetic components regulate gene expression in a spatiotemporal fashion remains partially known. Here, I generated 15 transgenic Arabidopsis GUS reporter lines for genes involved in DNA methylation and demethylation pathways. The spatiotemporal expression patterns of these genes were profiled in various plant organs during development, exogenous phytohormone response, and plant-parasitic nematode pathogenesis. The analyses revealed unique and overlapping expression patterns in roots, shoots, and reproductive organs, emphasizing the importance of a DNA methylation—demethylation equilibrium. …