Cell and Developmental Biology Commons^™

Putting A Bifunctional Motor To Work: Insights Into The Role Of Plant Kch Kinesins, Ram Dixit

Biology Faculty Research

Comment on: A novel actin-microtubule cross-linking kinesin, NtKCH, functions in cell expansion and division. [New Phytol. 2012 Feb;193(3):576-89. doi: 10.1111/j.1469-8137.2011.03944.x. ]

Single-Molecule Analysis Of The Microtubule Cross-Linking Protein Map65-1 Reveals A Molecular Mechanism For Contact-Angle-Dependent Microtubule Bundling, Amanda Tulin, Sheri Mcclerklin, Yue Huang, Ram Dixit

Biology Faculty Research

Bundling of microtubules (MTs) is critical for the formation of complex MT arrays. In land plants, the interphase cortical MTs form bundles specifically following shallow-angle encounters between them. To investigate how cells select particular MT contact angles for bundling, we used an in vitro reconstitution approach consisting of dynamic MTs and the MT-cross-linking protein MAP65-1. We found that MAP65-1 binds to MTs as monomers and inherently targets antiparallel MTs for bundling. Dwell-time analysis showed that the affinity of MAP65-1 for antiparallel overlapping MTs is about three times higher than its affinity for single MTs and parallel overlapping MTs. We also …

Expression Of 14-3-3 Protein Isoforms In Mouse Oocytes, Eggs And Ovarian Follicular Development, Santanu De, Jennifer Marcinkiewicz, Srinivasan Vijayaraghavan, Douglas Kline

Biology Faculty Articles

Background

The 14-3-3 (YWHA) proteins are a highly conserved, ubiquitously expressed family of proteins. Seven mammalian isoforms of 14-3-3 are known (β, γ, ε, ζ, η, τ and, σ). These proteins associate with many intracellular proteins involved in a variety of cellular processes including regulation of the cell cycle, metabolism and protein trafficking. We are particularly interested in the role of 14-3-3 in meiosis in mammalian eggs and the role 14-3-3 proteins may play in ovarian function. Therefore, we examined the expression of 14-3-3 proteins in mouse oocyte and egg extracts by Western blotting after polyacrylamide gel electrophoresis, viewed fixed …

Tumor Suppression By Cell Competition Through Regulation Of The Hippo Pathway, Chiao-Lin Chen, Molly C. Schroeder, Madhuri Kango-Singh, Chunyao Tao, Georg Halder

Biology Faculty Publications

Homeostatic mechanisms can eliminate abnormal cells to prevent diseases such as cancer. However, the underlying mechanisms of this surveillance are poorly understood. Here we investigated how clones of cells mutant for the neoplastic tumor suppressor gene scribble (scrib) are eliminated from Drosophila imaginal discs. When all cells in imaginal discs are mutant for scrib, they hyperactivate the Hippo pathway effector Yorkie (Yki), which drives growth of the discs into large neoplastic masses. Strikingly, when discs also contain normal cells, the scrib− cells do not overproliferate and eventually undergo apoptosis through JNK-dependent mechanisms. However, induction of apoptosis does …

[Accepted Article Manuscript Version (Postprint)] Plant Peroxisomes: Biogenesis And Function, Jianping Hu, Alison Baker, Bonnie Bartel, Nicole Linka, Robert Mullen, Sigrun Reumann, Bethany Zolman

Biology Department Faculty Works

Peroxisomes are eukaryotic organelles that are highly dynamic both in morphology and metabolism. Plant peroxisomes are involved in numerous processes, including primary and secondary metabolism, development, and responses to abiotic and biotic stresses. Considerable progress has been made in the identification of factors involved in peroxisomal biogenesis, revealing mechanisms that are both shared with and diverged from non-plant systems. Furthermore, recent advances have begun to reveal an unexpectedly large plant peroxisomal proteome and have increased our understanding of metabolic pathways in peroxisomes. Coordination of the biosynthesis, import, biochemical activity, and degradation of peroxisomal proteins allows for highly dynamic responses of …

Estradiol Modulation Of Calcium Dynamics In Pituitary Mmq Lactotroph Cells, Monika Pauckova

Electronic Theses and Dissertations

Pituitary lactotrophs are excitable cells that exhibit spontaneous, calcium influx triggering prolactin (PRL) secretion to stimulate lactation. Lactotrophs express estrogen receptors (ER) and are a well established estrogen-responsive cell system. 17B-estradiol (E2) is known to directly affect lactotrophs by increasing PRL transcription and biosynthesis, intracellular Ca2+ concentration ([Ca2+]i) and PRL secretion. This study demonstrates that the MMQ clonal cell line, isolated from the 7315a rat pituitary tumor, is a model lactotroph cell line that is E2-responsive. Spontaneous and evoked Ca2+ transients were especially sensitive to L-type channel block, but not affected by block of omega-conotoxin-GVIA-sensitive CaV channels or TTX-sensitive voltage-gated …

Biophysical And Biochemical Factors In The Cellular Microenvironment; Effects On Cell Migration And Invasion, Shalini Menon

Wayne State University Dissertations

Cellular migration is a vital process central to many physiological events including development, immune surveillance and wound healing. However, migration and invasion are not unique to normal physiology, they are also key determinants in the progression of disease states such as cancer. Given the significance of migration it is important that we understand how the process is regulated intracellularly and the various stimuli that can promote it. Even though the role of biochemical factors in mediating migration has been studied extensively, the role of biophysical factors in modulating migration and invasion is less appreciation. The biochemical and biophysical components of …

Understanding Fracture, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Standardised Classification Of Pre-Release Development In Male-Brooding Pipefish, Seahorses, And Seadragons (Family Syngnathidae), Stefan Sommer, Camilla M. Whittington, Anthony B. Wilson

Publications and Research

Background: Members of the family Syngnathidae share a unique reproductive mode termed male pregnancy. Males carry eggs in specialised brooding structures for several weeks and release free-swimming offspring. Here we describe a systematic investigation of pre-release development in syngnathid fishes, reviewing available data for 17 species distributed across the family. This work is complemented by in-depth examinations of the straight-nosed pipefish Nerophis ophidion, the black-striped pipefish Syngnathus abaster, and the potbellied seahorse Hippocampus abdominalis.

Results: We propose a standardised classification of early syngnathid development that extends from the activation of the egg to the release of newborn. The classification consists …

Inhibition Of Voltage-Gated Na+ Current By Nanosecond Pulsed Electric Field (Nspef) Is Not Mediated By Na+ Influx Or Ca²+ Signaling, Vasyl Nesin, Andrei G. Pakhomov

Bioelectrics Publications

In earlier studies, we found that permeabilization of mammalian cells with nsPEF was accompanied by prolonged inhibition of voltage-gated (VG) currents through the plasma membrane. This study explored if the inhibition of VG Na⁺ current (I_Na) resulted from (i) reduction of the transmembrane Na⁺ gradient due to its influx via nsPEF-opened pores, and/or (ii) downregulation of the VG channels by a Ca²⁺ -dependent mechanism. We found that a single 300?ns electric pulse at 1.65.3?kV/cm triggered sustained Na⁺ influx in exposed NG108 cells and in primary chromaffin cells, as detected by increased fluorescence of a …

The Development And Morphology Of Zebrafish After Embryonic Ethanol Exposure, Frances Lee

Honors Theses

Maternal consumption of alcohol may subject the fetus to fetal alcohol syndrome or fetal alcohol spectrum disorders (FAS or FASD). FAS/D is a public health problem, and affected children are defined by varying degrees of irreversible mental retardation, physical defects, behavioral issues, and vision problems from prenatal alcohol exposure (Riley et al. 2011). Recent studies on FAS have looked towards animal models, such as zebrafish, Danio rerio, that exhibit homologous physical and behavioral effects of alcohol (Bilotta et al. 2004). I exposed zebrafish embryos to low doses of ethanol (0.5% v/v or 1% v/v) in either chronic (at least 8 …

The Role Of An Rna Binding Protein Hnrnp K During Axon Development And Regeneration In Xenopus Laevis, Yuanyuan Liu

Legacy Theses & Dissertations (2009 - 2024)

Coordinated synthesis and assembly of the cytoskeletal network contribute significantly to morphological changes during axon outgrowth. Previous studies demonstrated that heterogeneous ribonucleoprotein K (hnRNP K), an RNA binding protein, binds to the 3'-untranslated regions of all neurofilament triplet subunits, the most abundant components of the axonal cytoskeleton. These findings raised the hypothesis that hnRNP K post-transcriptionally mediates the coordinated expression of axonal cytoskeletal components. In my thesis, I test this hypothesis during both axonal development and regeneration.

An Exhibit Wordle, Allison Marsh

Handouts

No abstract provided.

A Crossword Puzzle For Kids, Allison Marsh

Handouts

No abstract provided.

Word Find, Allison Marsh

Handouts

No abstract provided.

Images From The Exhibit, Page 1, Allison Marsh

Handouts

No abstract provided.

Lesson Plans, Activities, And Further Reading, Allison Marsh

Handouts

No abstract provided.

Why Do We Collect?, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.

Spotlight On Usc: A.C. Moore Herbarium, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.

Imaging And Aesthetics, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.

Listen, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Spotlight On Usc: Mechanical Engineering, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Photographic Evidence, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Influencing Art, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Conclusion Panel, Allison Marsh

Section 6: Conclusion

No abstract provided.

Cancer And You, Diah-Aldeen Judeh

A with Honors Projects

This project discusses ways a person can identify cancer and what to do if cancer is present.

Capturing Motion, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Images From The Exhibit, Page 2, Allison Marsh

Handouts

No abstract provided.

Inefficient Replication Reduces Reca-Mediated Repair Of Uvdamaged Plasmids Introduced Into Competent Escherichia Coli, Harout Arthur Jeiranian, Charmain T. Courcelle, Justin Courcelle

Biology Faculty Publications and Presentations

Transformation of Escherichia coli with purified plasmids containing DNA damage is frequently used as a tool to characterize repair pathways that operate on chromosomes. In this study, we used an assay that allowed us to quantify plasmid survival and to compare how efficiently various repair pathways operate on plasmid DNA introduced into cells relative to their efficiency on chromosomal DNA. We observed distinct differences between the mechanisms operating on the transforming plasmid DNA and the chromosome. An average of one UV-induced lesion was sufficient to inactivate ColE1-based plasmids introduced into nucleotide excision repair mutants, suggesting an essential role for repair …

Uvrd Participation In Nucleotide Excision Repair Is Required For The Recovery Of Dna Synthesis Following Uv-Induced Damage In Escherichia Coli, Kelley Nicole Newton, Charmain T. Courcelle, Justin Courcelle

Biology Faculty Publications and Presentations

UvrD is a DNA helicase that participates in nucleotide excision repair and several replication-associated processes, including methyl-directed mismatch repair and recombination. UvrD is capable of displacing oligonucleotides from synthetic forked DNA structures in vitro and is essential for viability in the absence of Rep, a helicase associated with processing replication forks. These observations have led others to propose that UvrD may promote fork regression and facilitate resetting of the replication fork following arrest. However, the molecular activity of UvrD at replication forks in vivo has not been directly examined. In this study, we characterized the role UvrD has in processing …