Department of Biological Sciences

/nsm/bio/

Biological Sciences Menu

/nsm/bio/

Giving

Contact Us

Main Campus
Wolfe Hall

Room 1235
Phone: 419.530.2065
Fax: 419.530.7737

webmaster@utoledo.edu

17thURS

17th Annual Undergraduate Research Symposium

Wolfe Hall Room 3246 Saturday April 14, 2012

2012 URS
URS 2012 Participants
L>R: Mike Borton, Lindsey Foster, Rob Puckett,
Amanda Kitson, Jordan Burlen, Andrew Stein, and Vanessea Gantz.

 

2012 URS winners
URS 2012 Winners
(L>R): Amanda Kitson (2nd), Andrew Stein (1st), and Lindsey Foster (3rd).

8:30-9:00 Coffee, Juice, and Bagels
9:00-9:05  Welcome. Dr. John Plenefisch, Associate Chair, Department of Biological Sciences.
9:10-9:30  Jordan Burlen, Proper Localization of Borealin to the Centromere Advisor: Dr. William R. Taylor, Department of Biological Sciences.
9:30 -10:50 Michael T. Borton The Functional Regulation of Chromosomal Passenger Protein Borealin  Advisor: Dr. William R. Taylor, Department of Biological Sciences.
9:50-10:10   Andrew Stein, The tyraminergic inhibition of aversive responses in C. elegans requires neuropeptides and mimics noradrenergic anti-nociception in mammals Advisor: Dr. Richard Komuniecki, Department of Biological Sciences.
10:10- 10:30 Lindsey Foster, Regulation of MLK1 and MLK4 Protein Levels in T98G Glioblastoma cells Advisor: Dr. Deborah Chadee, Department of Biological Sciences.
10:30 - 10:45 Break
10:45-10:05  Vanessa Gantz Interaction Between Protein 2 and Protein 6 of Cauliflower mosaic virus. Advisor: Dr. Scott Leisner, Department of Biological Sciences.
10:05-11:25 Robert Puckett Identification of genes that are essential for correct intermediate filament localization in C. elegans Advisor: Dr. John Plenefisch, Department of Biological Sciences.
11:25-11:45  Amanda Kitson Influence of Histone Deacetylases (HDACs) on NF-κB Activity Advisor: Dr. Brian Ashburner, Department of Biological Sciences.
11:45-12:10  Pizza Lunch
12:10-12:30  Awards Ceremony and Pictures

        Abstracts

Proper Localization of Borealin to the Centromere

 

Jordan J. Burlen

Department of Biological Sciences

Faculty Advisor: Dr. William R. Taylor

 

Cancer is characterized by uncontrolled cell proliferation. Greater understanding of nuclear and cytoplasmic division can identify cures for cancer and other diseases. The cell cycle is composed of interphase, mitosis, and cytokinesis. This process results in the formation of two identical daughter cells. Errors in cell cycle regulation can result in cancer. Incorrect microtubule attachment to kinetochores can cause separation errors of the sister chromatids, resulting in aneuploidy (an abnormal number of chromsomes). Oncogenesis is a possible result of aneuploidy. Incorrect microtubule attachment to kinetochores can cause separation errors of the sister chromatids.

The chromosomal passenger complex (CPC) prevents non-bipolar attachments by detecting and destabilizing them. The enzymatic subunit of the CPC that is involved in this process is the Aurora B kinase. The other members of the CPC include INCENP (an inner centromere protein), Survivin (a member of the inhibitor of apoptosis (IAP) family), and Borealin. The CPC localizes at the inner centromere early in mitosis. This localization is necessary for proper CPC function and chromosome segregation.

The role of Borealin is not fully understood. The function of the C-terminus of Borealin was studied by creating 124 AA and 110 AA truncations via polymerase chain reaction (PCR). Various members of Dr. William Taylor’s lab used these truncations to study the localization and function of Borealin. The 110 AA truncation localized to the centromere in immunoflorescence and cell cycle analysis. This suggests that the C-terminus, under the conditions analyzed, is nonessential for localization of Borealin to the centromere.

The Functional Regulation of Chromosomal Passenger Protein Borealin

Michael T. Borton

Department of Biological Sciences

Faculty Advisor: Dr William R. Taylor

 

The Spindle Assembly Checkpoint (SAC) is an evolutionarily conserved cell cycle control mechanism that prevents premature sister chromatid separation during mitosis.  The Chromosomal Passenger Complex (CPC) regulates SAC activation and consists of INCENP, Survivin, Borealin, and Aurora B Kinase. The CPC localizes to centromeres to ensure correct kinetochore-microtubule attachment.  Borealin localization to centromeres is regulated by phosphorylation; however, the opposing phosphatase that regulates Borealin dephosphorylation is unknown.  Mobility shift for Borealin in human cells containing knockouts for phosphatase Cdc14A or Cdc14B show no difference in Borealin expression.  In comparison, phosphatase inhibitor okadaic acid does delay the dephosphorylation of Borealin as cells exit mitosis suggesting that the phosphatase PP2A may be responsible for the dephosphorylation of Borealin. Additionally, Borealin protein stability is regulated; yet, the mechanisms that govern Borealin stability are unknown.  Increased levels of Borealin are found in samples containing proteasome inhibitor MG132, though the structurally different proteasome inhibitor Lactacystin did not suppress degradation suggesting that a protease other than the proteasome may be responsible for Borealin degradation.  Finally, Borealin localization to centromeres is mediated by phosphorylation of histone H2A (pH2A).  ChIP analysis of Borealin and pH2A indeed indicates that both localize primarily at the centromere of DNA. 

The tyraminergic inhibition of aversive responses in C. elegans requires neuropeptides and mimics noradrenergic anti-nociception in mammals

Andrew M. Stein

Department of Biological Sciences

Faculty Advisor: Dr. Richard Komuniecki

 

 

In the nematode model system, Caenorhabditis elegans, the monoamines, tyramine (TA) and octopamine (OA), invertebrate counterparts of epinephrine and norepinephrine, respectively, appear to independently activate global peptidergic signaling cascades that inhibit aversive responses to noxious stimuli mediated by two ASH sensory neurons. To better understand the complex role of peptidergic signaling in this monoamine-dependent inhibition, we examined the roles in individual neuropeptides expressed in the TA-sensitive ASI sensory neurons on various aspects of locomotory behavior. Peptides encoded by nlp-14were essential for the TA inhibition of aversive responses and animals overexpressing nlp-14 moved more slowly and reversed less frequently than wild type animals off but not on food. These results confirm that 1) the TA-dependent release of individual peptides from the ASIs is essential for the TA inhibition of aversive responses and 2) these peptides may have additional more wide-spread roles in modulating locomotory behavior. TA/OA inhibition of aversive responses mimics mammalian noradrenergic antinociception and suggests that C. elegans may be a useful model for understanding the noradrenergic modulation of chronic pain in mammals.

Regulation of MLK1 and MLK4 Protein Levels in T98G Glioblastoma cells

Lindsey A. Foster

Department of Biological Sciences

Faculty Advisor: Dr. Deborah N. Chadee

 

            Mixed-lineage kinases (MLKs) are serine/threonine protein kinases that are classified as mitogen-activated protein kinases (MAPKs) that function in signal transduction. Eukaryotic cells have conserved MAPK signaling pathways in order to respond to a variety of extracellular stimuli and control the regulation of biological processes. MLK3 is a client protein of the molecular chaperone Hsp90. Hsp90 interacts with and stabilizes client proteins.

Interaction Between Protein 2 and Protein 6 of Cauliflower mosaic virus

Vanessa Gantz

Advisor: Dr. Scott Leisner

Plant viruses can cause massive problems within a population by causing disease that could potentially wipe out crops. Cauliflower mosaic virus (CaMV) is a plant pararetrovirus infecting plants in the mustard family. The CaMV 8 kb circular double-stranded DNA genome encodes for seven viral proteins (P1-P7).  CaMV P6, inclusion body protein, encoded by gene VI, is implicated in a variety of functions such as: host range determination, symptom formation, resistance breakage, host hypersensitive responses, and virus viability.  In addition, P6 functions as the translational transactivator, meaning it is required for translation of all CaMV proteins from a polycistronic viral RNA.  CaMV P2, encoded by gene II, is essential for aphid transmission of the virus.  CaMV has multiple virus strains; our research focuses on the viral isolates CM1841 and W260.  Previous work has suggested that W260 possesses more stable inclusion bodies and produces more severe viral symptoms than its CM1841 counterpart.  P2 has been proposed to influence P6 inclusion body stability. However a direct interaction between P2 and P6 has not previously been demonstrates. Therefore, yeast two-hybrid analysis was performed to determine if there was an interaction between P2 and P6.  To test this interaction, CaMV P2 from two different viral isolates, W260 and CM1841, were examined for interaction with P6.  The results from yeast two-hybrid analyses showed that P2 proteins from both viral isolates bind to P6.  In addition, W260 P2 had an increased binding efficiency to P6 when compared to CM 1841 P2.  Our data suggests that perhaps the increased stability of the W260 P2-P6 interaction may contribute to the more stable inclusion bodies.

Identification of genes that are essential for correct intermediate filament localization in C. elegans

 

Robert Puckett

Department of Biological Sciences

Faculty Advisor: Dr. John Plenefisch

 

 

 

            ifa-2 is a member of the mua (muscle attachment abnormal) family of genes of Caenorhabditiselegans and is known to encode the cytoplasmic intermediate filament IFA-2. This family of genes are involved in connecting skeletal muscle tissue to the cuticle across the intervening epidermis through hemidesmosomes and their associated intermediate filaments. Mutations in ifa-2 cause these connections to become fragile and fail, resulting in separation of the muscles from the body wall and locomotory defects in the worm. Proteins of the hemidesmosome are likely to be  involved in the proper localization of IFA-2. By using RNA interference (RNAi), a simple procedure that prevents the translation of a specific mRNAs, I can target specific hemidesmosome or other IFA-2 associated proteins for reduced expression. I am looking at both proteins known to be associated with muscle attachment and those suspected to be associated with IFA-2 based on the results of a yeast 2-hybrid study by graduate student Kyle Walker. These include KO4G7.1, let-805b, let-805c, let-805d, vab-10a, vab-10b, vab-19, pat-12j, and pat-12j. The feeding RNAi experiment is being performed on a line of worms that express an IFA-2::GFP fluorescent reporter protein, thereby allowing me to observe whether knock-down of expression of any of the proteins results in  mislocalization of IFA-2 and concomitant of muscle attachment defects using a fluorescent microscope.

Influence of Histone Deacetylases (HDACs) on NF-κB Activity

Amanda Kitson

Dr. Brian Ashburner

Dept. of Biological Sciences

 

Nuclear factor-κB (NF-κB) is a transcription factor that regulates various cellular processes including cell proliferation and programmed cell death (apoptosis).  Once inside the nucleus, NF-κB can interact with coactivators and corepressors to control the expression of genes within the cell.  Histone deacetylases (HDACs), which increase chromatin compaction on nucleosomes, can repress NF-κB activity, although further research must be conducted to better understand this relationship.  Using wild-type HeLa cells as a control against HeLa HDAC1-knockdown cells, HDAC2-knockdown cells, and HDAC3-knockdown cells, this project studied the effects and roles and HDAC1, HDAC2, and HDAC3 in the repression of NF-κB after treatment with tumor necrosis factor α.  Conduction of Western Blots with cytoplasmic and nuclear extracts of the cell samples permitted observation of the movement of p65, IκBα, and IKKα within the cells.  Upon examination of the results, the HDAC3-KD cells showed decreased presence of IκBα in the cytoplasm compared to the control cells and HDAC1-KD and HDAC2-KD cells.  The results suggest that HDAC3 must play a role in the repression of NF-κB through its relationship with IκBα.  Further research must be conducted to gain a clear picture of the relationship of the HDACs and NF-κB.
Last Updated: 6/26/15