DEPARTMENT OF BIOLOGY FACULTY PROFILE
RESEARCH HEMAYET ULLAH PUBLICATIONS
Contact Information
E-mail: hullah@howard.edu
Office Location: EE Just Hall Room 314
Office Telephone: 202-806-6958
Laboratory Location: EE Just Hall Room 323
Link to Google Scholar: Hemayet Ullah

Education
B.S.,
M.S., North Carolina State University (1998)
Ph.D., University of North Carolina, Chapel Hill (2002)


Courses
Molecular Biology of the Cell (532)
Molecular Physiology of Plants (460)

Research Interests
Cellular signal transduction pathways
Receptor for Activated Kinase C (RACK1) and G proteins
Plant biology and Arabidopsis

Grants and Funding Awards
NSF | RACK1 Proteins in Stress Signaling Pathways
NSF | Mentoring in Environmental Biology (URM)
Plant Science as STEM (NSF: HBCU-UP Targeted Infusion Project


Laboratory Personnel
Denver Baptiste - Graduate Student
Mercy Sabila - Graduate Student
MD Ahasanur Rahman - Graduate Student
Albandari Albehishi- Graduate Student

Research Detailed
Heterotrimeric G-protein mediated cellular signal transduction pathway is the dominant mode of transducing extracellular signal inside the cell. Although the presence of G-protein coupled signal transduction is well documented in diverse biological systems, evidence for a comparable system in plants has just started to accumulate. By utilizing G-protein knock-out alleles in Arabidopsis, our previous works have unraveled diverse G-protein dependent signaling pathways, ranging from auxin, brassinosteroid, gibberellin, ABA, and water-stress. At present, my lab is interested in elucidating the cellular signal transduction pathways mediated by Receptor for Activated Kinase C (RACK1)- a structural homolog of G-protein beta subunit. Major function of RACK1 is perceived to be the integration of signals from different pathways by acting as a scaffold protein. The repertoire of non-plant RACK1 interacting proteins that contain diverse partners ranging from kinases, phosphatases, heterotrimeric G-proteins, ion channels, ribosomes, and membrane and nuclear receptors, established the protein as a multipurpose protein. Though three distinct RACK1 genes, as opposed to a single gene in non-plant organisms, are present in Arabidopsis, essentially nothing is known about their cellular functions. A combination of molecular genetic and cell biological approaches are being utilized to unravel the plant RACK1-mediated signaling pathways. Preliminary results from gene knock-out characterizations implicate RACK1 in plant signaling pathways that are not present in other organisms. Therefore, plant RACK1 studies provide unique opportunities to unravel novel roles for the protein.

'Drugs' increase photosynthetic capability
Patent-pending drought resistant gene modification

'Drugs' increase photosynthetic capability- Oxygen generated during photosynthesis make green leaves buoyant

At present, our lab efforts are geared toward developing technology to address drought and salt stress resistance in crop plants. Farmers of developing world suffer disproportionately during environmental stresses induced crop loss. Genetic knock-out of Arabidopsis RACK1A gene confers drought and salt stress resistance.   It is hypothesized that chemical knock-out, as opposed to genetic knock-out, of RACK1A will provide a functional advantage in protecting plants from these stresses (circumventing GMO approach). Based on our deduced crystal structure, small compound library screen (Dr. Dakshanamurthy) resulted in isolating several small RACK1A ‘inhibitor’ compounds that confer drought and salt stress resistance in diverse crop plants. With proper chemistry, the patented compounds await field trials as for their potential to apply safely like fertilizer.

Field: Agricultural, Biotechnology, Energy. Technology: Genetically modified crops with drought-resistant traits, and potential resistance to other harsh environmental conditions. Key Features:-Produces drought-resistant plants, Applicable to food and biofuel crops. Result of a novel discovery of a gene function that is not presently exploited for drought-resistance. Stage of Development:Proof of concept demonstrated in Arabidopsis

Selected Publications

  Ogunwuyi, O., Upadhyay, A., Adesina, S.K., Puri, R., Foreman, T.M., Hauser, B.R., Cox, J., Afoakwah, E., Porter, A., Annan, E., Manka, C., Olatilewa D., Thompson, B., Kibanyi, P.K., Miller, K., and Ullah, H. (2016) Genomic Imprinting: Comparative Analysis Between Plants and Mammals. Plant Tissue Cult. & Biotech. 26(2): 267-284 (December)
  Villanueva MA, Islas-Flores T and Ullah H (2016). Signaling through WD-repeat proteins in plants. Front. Plant Sci. 7:1157.doi: 10.3389/fpls.2016.01157
  Sabila M, Kundu N, Smalls D and Ullah H (2016). Tyrosine Phosphorylation Based Homo-dimerization of Arabidopsis RACK1A Proteins Regulates Oxidative Stress Signaling Pathways in yeast.. Front. Plant Sci. 7:176. doi: 10.3389/fpls.2016.00176
  Flores, T. I., Rahman, A., Ullah, H., Villanueva, M. A. (2015) The Receptor for Activated C Kinase in Plant Signaling: Tale of a Promiscuous Little Molecule. Frontiers in Plant Science 6.
  Elizondo, D; Fernando, L. M; Oliver, E; Clinton, K; Retland, N; Paturault, H; and Ullah, H (2015) Welcome to the Brave New World: CRISPR mediated Genome Editing- pathway to designer babies? Plant Tissue Cult. & Biotech. 25(1): 143-154
  Kundu N., Dozier U., Deslandes L., Somssich IE, Ullah, H (2013) Arabidopsis scaffold protein RACK1A interacts with diverse environmental stress and photosynthesis related proteins. Plant Signal Behav. May 2013 Vol 8 (5)
  Fennell, H., Olawin, A., Mizanur, R., Ken, I., Chen, JG., Ullah, H. (2012) Arabidopsis scaffold protein RACK1A modulates rare sugar D-allose regulated gibberellin signaling. Plant Signal Behav. 2012 Sep 5;7(11).
Ullah, H., Scappini, E., Moon, AF., Williams, LV., Armstrong, DL., and Pedersen, LC (2009) Crystal Structure of a signal transduction regulator, RACK1 from Arabidopsis thaliana. Protein Sci.17(10):1771-80. (on cover page)
  Magee, K., Michael, A., Ullah H., and Dutta, SK. (2007) Dechlorination of PCB in the presence of plant nitrate reductase. Environmental Toxicology and Pharmacology25:144-147
  Chen JG, Ullah H, Temple B, Liang J, Guo J, Alonso JM, Ecker JR, Jones AM. (2006) RACK1 mediates multiple hormone responsiveness and developmental processes in Arabidopsis. J Exp Bot, 57: 2697-2708.

  Nina M. Storey, NM., Gentile, S., Ullah, H.,Russo, A., Muessel, M., Erxleben, C., and Armstrong, DL. (2006) Rapid signaling at the plasma membrane by a nuclear receptor for thyroid hormone. Proceedings of the National Academy of Sciences, USA. 103: 5197-5201.
  Jones AM, Ullah H, and Chen JG (2003) Dual Pathways for Auxin Regulate Cell Division and Expansion. ed. Nagata, T. Biotechnology in Agriculture and Forestry (Series), .Springer Press. Vol. 53, 181-191.(Book Chapter)
  Ullah H, Chen JG, Temple B, Alonso J, Ecker J, Boyes D, Davis K, and Jones AM (2003) Auxin Signaling Coupled by Heterotrimeric G protein in Arabidopsis Lateral Root Formation. Plant Cell 15, 393-409.
  Ullah H, Chen JG, and Jones AM (2002) Role of GPA1 in Regulation of Arabidopsis Seed Germination. Plant Physiology 129, 897-907.
  Chen JG, Ullah H, Young JC, Sussman MR, Jones AM (2001) ABP1 is Required for Organized Cell Elongation and Division in Arabidopsis Embryogenesis. Genes & Development 15, 902-911 (on cover page)
  Ullah H., Chen JG, Young JC, Im KH, Sussman MR, and Jones AM (2001) Modulation of Cell Proliferation by G-protein Alpha Subunit in Arabidopsis. Science 292, 2066-2069.
  Ullah H, Clark G, and Islam AS (2001) Internet Resources for Molecular Biology: A Primer for Scientists from Least Developed Countries. Plant Tissue Cult. 11, 195-208, 2001.
  Wang XQ, Ullah H, Jones AM, and Assmann S (2001) G protein Regulation of Ion Channels and Abscisic Acid Signaling in Arabidopsis Guard Cells. Science 292, 2070-2072.>