Developmental Biology Commons^™

Variable Levels Of Drift In Tunicate Cardiopharyngeal Gene Regulatory Elements, W. Colgan, A. Leanza, A. Hwang, M. B. Debiasse, Isabel Llosa , '20, Daniel Rodrigues , '21, Hriju Adhikari , '20, Guillermo Barreto Corona , '19, Saskia Bock , '20, Amanda T. Carillo-Perez , '19, Meagan Currie , '20, S. Darkoa-Larbi, D. Dellal, Hanna Gutow , '20, P. Hokama, E. Kibby, N. Linhart, S. Moody, Allison Naganuma , '20, D. Nguyen, Ryan Stanton , '20, S. Stark, Cameron Tumey , '21, A. Velleca, J. F. Ryan, Bradley Justin Davidson , '91

Biology Faculty Works

Background: Mutations in gene regulatory networks often lead to genetic divergence without impacting gene expression or developmental patterning. The rules governing this process of developmental systems drift, including the variable impact of selective constraints on different nodes in a gene regulatory network, remain poorly delineated. Results: Here we examine developmental systems drift within the cardiopharyngeal gene regulatory networks of two tunicate species, Corella inflata and Ciona robusta. Cross-species analysis of regulatory elements suggests that trans-regulatory architecture is largely conserved between these highly divergent species. In contrast, cis-regulatory elements within this network exhibit distinct levels of conservation. In particular, while most …

Modeling Collective Migration Of Neural Crest Cells With A Cucker-Smale Velocity Alignment Process, Claire Evensen

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Connective Tissue Fibroblasts From Highly Regenerative Mammals Are Refractory To Ros-Induced Cellular Senescence, Sandeep Saxena, Hemendra J. Vekaria, Patrick G. Sullivan, Ashley W. Seifert

Biology Faculty Publications

A surveillance system in mammals constantly monitors cell activity to protect against aberrant proliferation in response to damage, injury and oncogenic stress. Here we isolate and culture connective tissue fibroblasts from highly regenerative mammals (Acomys and Oryctolagus) to determine how these cells interpret signals that normally induce cellular senescence in non-regenerating mammals (Mus and Rattus). While H₂O₂ exposure substantially decreases cell proliferation and increases p53, p21, p16, and p19 in cells from mice and rats, cells from spiny mice and rabbits are highly resistant to H₂O₂. Quantifying oxygen consumption …

Fgf-Signaling Is Compartmentalized Within The Mesenchyme And Controls Proliferation During Salamander Limb Development, Sruthi Purushothaman, Ahmed Elewa, Ashley W. Seifert

Biology Faculty Publications

Although decades of studies have produced a generalized model for tetrapod limb development, urodeles deviate from anurans and amniotes in at least two key respects: their limbs exhibit preaxial skeletal differentiation and do not develop an apical ectodermal ridge (AER). Here, we investigated how Sonic hedgehog (Shh) and Fibroblast growth factor (Fgf) signaling regulate limb development in the axolotl. We found that Shh-expressing cells contributed to the most posterior digit, and that inhibiting Shh-signaling inhibited Fgf8 expression, anteroposterior patterning, and distal cell proliferation. In addition to lack of a morphological AER, we found that salamander …

Towards A Mathematical Model Of Motility Using Dictyostelium Discoideum: Proteins And Geometric Features That Regulate Bleb-Based Motility, Zully Santiago

Dissertations, Theses, and Capstone Projects

A variety of biological functions depend on actin organization. The organization of actin is tightly regulated by a plethora of extracellular and intracellular signaling, scaffolding, and actin-binding proteins. Dysfunctions in this regulation lead to immune diseases, increased susceptibility to pathogens, neurodegenerative diseases, developmental disorders, and cancer metastasis. A variety of actin-dependent processes, including cell motility, are regulated by several proteins of interest: Paxillin, a scaffolding protein; WASP, an actin nucleating protein; SCAR/WAVE, another WASP family actin nucleating protein; Talin, a cortex-to-membrane binding protein; Myosin II, an F-actin contracting motor protein; and Protein Kinase C, a protein kinase. D. discoideum cells …

The Influence Of Mir-322 On Skeletal Muscle Differentiation, Miles Alexander Soyer

Legacy Theses & Dissertations (2009 - 2024)

Skeletal muscle plays a crucial role in coordinating voluntary movement and accounts for nearly 50% of total body mass. Dysregulation in skeletal muscle development is known to cause muscle degenerative diseases including the devastating Duchenne Muscular Dystrophy (DMD). The majority of the biological studies investigating muscle development were based on myogenic transcription factors and signaling molecules including: Pax7, Myf5, MyoD, WNT, TGF-β and BMP. After the discovery of non-coding RNAs including microRNAs, it was postulated that these molecules could regulate gene expression and thus affect differentiation and development. MicroRNAs are small non-coding RNAs (~17-25 nucleotides) that regulate gene expression negatively …

The Functional Conservation Of Frazzled In Insects, Benjamin Wadsworth

Graduate Theses and Dissertations

Axons in the developing embryo receive and react to signals that direct their growth to reach target tissues at specified locations. The signal pathways that direct midline crossing of axons during embryonic development have been comprehensively examined in the past years using the Drosophila ventral nerve cord or the spinal cord as a model system. A number of these signaling mechanisms are conserved, however disparities have been found between species in general strategy or the molecular signals controlling the response of axons to guidance cues.

The Netrin-Frazzled pathway has been shown to aid in midline crossing of axons in the …

Understanding The Molecular And Cellular Functions Of Odd-Skipped Related 1 In Outflow Tract Development, Menglan Xiang

Theses and Dissertations

The cardiac outflow tract (OFT) is a transient conduit that connects the embryonic heart chambers to the vascular network. Transcription factor Osr1 promotes the proliferation and cell cycle progression of second heart field (SHF), an essential cell population that contribute to the developing OFT. In this study, we investigated the role of Osr1 in OFT development on cellular and molecular levels using a systems biology approach. We observed OFT rotation and elongation defects, as well as double-outlet right ventricle and overriding aorta as a result of SHF-specific deletion of Osr1. Using genetic inducible fate mapping, we showed that Osr1-expressing SHF …

Knocking Out A Negative Regulator Of Hedgehog Signaling Blocks Differentiation Of Cells Into Neurons, Danielle Margaret Spice, Gregory M. Kelly Ph.D.

Western Research Forum

Hedgehog (Hh) signaling, one of many different protein signaling pathways found in mammals, is vital in many stage of neural development. A major negative regulator of Hh signaling is a protein known as Suppressor of Fused (SUFU), which acts to sequester the full length Gli transcription factors, proteins that can turn genes on and off, in the cytoplasm or facilitates its conversion to a repressive form. The P19 embryonal carcinoma cell line is a model of hind-brain neuronal differentiation and the involvement of Hh signaling, in particular the role of SUFU in this process has yet to be explored. We …

Glial Bridge Development: 26 Hpf, Barresi Lab, Smith College

Glial Bridge

No abstract provided.

Glial Bridge Development: 24 Hpf, Barresi Lab, Smith College

Glial Bridge

No abstract provided.

Glial Bridge Development: 30 Hpf, Barresi Lab, Smith College

Glial Bridge

No abstract provided.

Glial Bridge Development: 28 Hpf, Barresi Lab, Smith College

Glial Bridge

No abstract provided.

Slit1a Rescue: Role Of Slit1a, Hss1a, Barresi Lab, Smith College

Role of slit1a

No abstract provided.

Slit1a Rescue: Role Of Slit1a, Hss1ayot, Barresi Lab, Smith College

Role of slit1a

No abstract provided.

Slit1a Rescue: Role Of Slit1a, Non-Hss1ayot, Barresi Lab, Smith College

Role of slit1a

No abstract provided.

Slit1a Rescue: Role Of Slit1a, Wt, Barresi Lab, Smith College

Role of slit1a

No abstract provided.

Validation Experiment: Wild Type, Raw, Gfap, Barresi Lab, Smith College

Validation Experiment

No abstract provided.

Validation Experiment: Wild Type, Psi, Barresi Lab, Smith College

Validation Experiment

No abstract provided.

Glial Bridge Development: 22 Hpf, Barresi Lab, Smith College

Glial Bridge

No abstract provided.