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UScholar Lunches

The UScholar lunches are your opportunity to learn about the work of other UScholars while enjoying FREE FOOD. UScholar students and faculty meet for lunch every Friday to hear a student or UScholar alum present his or her research and answer any questions.

TIME: Fridays at noon
PLACE: Fireside Room, 2nd Floor of the ARCH building
SPEAKERS: If you are interested in presenting, contact . For presentation guidelines, click here

Hear Penn’s Undergraduate Research Award recipients and Penn’s University Scholars discuss their work while enjoying a catered lunch! Fridays at noon in the Fireside Room (unless otherwise noted).

This semester’s speaking schedule:

January 13
Yujing Chung

Hypoxia Inducible Factors (HIFs) are transcription factors that respond to changes in oxygen in the cellular environment. A central element of the oxygen-sensing pathway is the family of enzymes known as the Prolyl Hydroxylase Domain proteins (PHD)¬, which hydroxylates the oxygen sensitive αsubunit of HIF on two prolyl residues– Pro402 and Pro564. This site-specific modification to HIFα allows recognition by the von Hippel Lindau tumor suppressor protein (VHL), a component of the E3 ubiquitin ligase complex that targets HIF-α for constitutive degradation by the ubiquitin-proteasome pathway.
Both PHD2 and VHL are negative regulators of HIF-α, where a loss of function of either PHD2 or VHL leads to the stabilization of HIF-α, thereby causing the irregular up-regulation of HIF target genes, such as EPO. Both mutations in VHL and PHD2 have been reported to result in either a partial loss of function, leading to erythrocyotosis, or a complete loss of function, predisposing to cancer.
More recently, studies have identified mutations in the HIF-2α gene as a third cause of erythrocytosis attributed to defects in the oxygen-sensing pathway. Evidence that implicates HIF-2α as the central HIF-α isoform regulating EPO in human adults comes from observations that mutations in the HIF-2α gene are associated with cases of erythrocytosis. All reported mutations to date are heterozygous missense mutations that affect residues that are C-terminal to the primary hydroxylation site in HIF-2α which have been found to hinder the interaction with PHD2 and/or VHL. A new heterozygous mutant, F540L, has recently been identified by Dr. Melanie Percy and colleagues of Belfast City Hospital and Queen’s University Belfast (personal communication to Dr. Frank S. Lee), in a patient with erythrocytosis. Similar to all reported cases, the affected residue in question, Phe540→Leu, is C-terminal to the primary hydroxylation site in HIF-2α. The objective was to determine if the mutation produces a functional defect in the interaction with PHD2 and/or VHL.

January 20
Paul Mitchell

January 27
Karthik Kumar

February 3
Marcel Salas

February 10
Arithruth Reyes

February 17
Michael Masciandaro

February 24
Eliana Ritts

March 2
Adam Haque

March 9
Spring Break

March 16
Lauren Corallo

March 23
Alicia Demaio

March 30
TBD

April 6
TBD

April 13
Alex Savoy-Knitter

April 20
TBD

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