Ira O. Daar, Ph.D.
In our laboratory, we focus on the Eph/ephrin signaling system, and specifically how the ephrinB transmembrane ligands for Eph receptor tyrosine kinases send signals affecting cell-cell junctions and cell movement. This signaling affects morphogenesis during development and has been shown to play an instructive role in angiogenesis, as well as tumor cell invasion.
1) Xenopus embryogenesis, 2) development, 3) signal transduction, 4) Eph/ephrin,
5) cell-cell adhesion, 6) cell migration
Developmental Signal Transduction
Cell-cell adhesion maintains intercellular connections between neighboring epithelial cells for normal morphogenetic movements during development. Disruption of this critical process is also one of the earliest steps in metastatic progression of cancer cells. Our laboratory has focused on providing mechanistic insights into how the Eph/ephrin signaling system affects cell-cell interactions; specifically, how the ephrinB transmembrane ligands send signals affecting cell-cell junctions, adhesion, and cell movement. This signaling affects morphogenesis during development, as well as tumor cell invasion in the disease state. We often employ the Xenopus system since we have found it to be a powerful tool for understanding the contribution of several signaling molecules to developmental and cellular processes. Thus, Eph/ephrin and Wnt/Planar Cell Polarity signal transduction can be assessed morphologically, histologically, as well as biochemically in a developing vertebrate. Although the bidirectional signaling between ephrinBs and their receptors is quite complex, it is clear that control of the expression and interplay between these proteins may have important effects on malignant transformation and metastatic progression. Our future direction is aimed toward a mechanistic understanding of the cross-talk between the Wnt and Eph/Ephrin systems; using an interdisciplinary approach to research by integrating the use of biochemical and developmental techniques to further our studies.
Selected Key Publications
Developmentally regulated GTP-binding protein 1 modulates ciliogenesis via an interaction with Dishevelled.Journal of Cell Biology. 218 issue 8: 2019. [ Journal Article ]
TBC1d24-ephrinB2 interaction regulates contact inhibition of locomotion in neural crest cell migration.Nature Commun. 9: 3491, 2018. [ Journal Article ]
- Oncogene. 37: 861-872, 2018. [ Journal Article ]
EphrinB1 interacts with CNK1 and promotes cell migration through c-Jun N-terminal kinase (JNK) activation..Journal of Biological Chemistry. 289: 18556-68, 2014. [ Journal Article ]
- Nat Commun. Mar 24;5:3516. doi: 10.1038/ncomms4516: 2014. [ Journal Article ]
Dr. Ira Daar obtained his Ph.D. degree from the State University of New York at Buffalo under the supervision of Dr. Lynne Maquat. There he investigated the molecular defects underlying common glycolytic enzyme deficiencies, and performed some of the earliest studies on nonsense- mediated mRNA decay. He obtained his postdoctoral training with Dr. George Vande Woude at NCI, investigating signal transduction events and cell cycle control points influenced by oncogene function. His present work focuses on signal transduction pathways that regulate cell-cell adhesion and cell movement.
|Jaeho Yoon, Ph.D.||Staff Scientist|
|Moonsup Lee Ph.D.||Postdoctoral Fellow (CRTA)|
|Yoo-Seok Hwang Ph.D.||Research Biologist|
|Jian Sun Ph.D.||Postdoctoral Fellow (Visiting)|
|David DeLaRosa B.S.||Postbaccalaureate Fellow (CRTA)|
|Leena Pade M.S.||Predoctoral Visiting Fellow (Graduate Student), UMD-NCI Partnership for Integrative Cancer Research|
Daar Lab - Summer 2019 - Front Row: Zoe Poppert, Jerlin Garo, Bhuvana Pandalai, Heather Rogers, Rachel Beall. Back Row: Jian Sun, Rich Hwang, Moonsup Lee, Jaeho Yoon, Hongchan Lee, Ira Daar. Olivia Stevens (not in photo).
Welcome new Werner H. Kirsten Student Interns! Artistry by Rachel Beall and Heather Rogers.
Daar Lab attends Mt. Sinai School of Medicine XenoTreat 2019 - Round Top, NY
The Lab 2019
Xenotreat Round Top, New York 2018
Students of Summer 2018
Back Row - Eric Gu, Rachel Beall, Heather Rogers, Tiana Fitzgerald
Front row - Hannah Jo, Maddy Salehi, Kim Grasmick
Xmas Lab Wing Party 2018
A Merry Frog Xmas
CDBL Holiday Party 2018
The Gang of Summer 2017
Alexi's Poster Presentation - WHK High School Intern 2016 - 2017
The Gang of Summer 2015
From L -> R: Rich Hwang (Staff Scientist), Katchya Acharya (Summer Student),
Kathy Soria (Lab Tech), Dili Sundaramoorthy (Postbac), Moon Sup Lee (Postdoc),
Jillian Kunze (High School Intern), Claire Scott (Summer Student), Jaeho Yoon (Postdoc),
Daniel Yoon (no relation to Jaeho) (High School Intern), Chu Bong (Summer Student), Ira Daar (PI)
Lab - Summer of 2013
How many of our brightest kids does it take to change an N2 tank?
The Kids of Summer: Alex, JJ, Olivia, and Katy hangin' out!
Yoo-Seok says, "You don't know what I am thinking!"
Our Frog Decor
Frog Lamp by Rachel Beall, WHK Summer Intern 2019
Princess Leia Frog, former Daar Lab mascot