Research Interests

Pattern Formation and Development

Changing patterns of morphological structure, appearance of new macromolecular entities and patterns of localization of macromolecules are hallmarks of the developmental process. In my lab, the expression pattern, structure and function of storage proteins during animal development is a major focus. The abundance and large size of storage proteins make them attractive models for studying cellular localization phenomena. Many storage proteins are synthesized in one tissue, secreted into circulation and subsequently taken up by another tissue for utilization. This provides abundant questions of cellular and subcellular mechanisms of spacial and temporal patterns. Several of these proteins have homologues throughout the animal kingdom and the evolution of their structure and regulation interests us. The massive amount of storage proteins that are produced suggests that they are limiting factors in the survival of animals. We have begun a study of natural variation in amounts of stored proteins in eggs and serum of economically important animals. One species, the American lobster, Homarus americanus (Decapoda), is under substantial commercial harvest pressure. Understanding of the events leading up to ovulation and molting may help the lobster fishermen to leave more non-commercial lobsters at sea. In winter flounder, Pleuronectes americanus, embryonic utilization of egg proteins may provide a means to monitor normal and abnormal development during early embryogenesis in this bottom feeding organism which lives in the estuaries adjacent to sources of pollution. In Atlantic cod, Gadus morhua, measuring the serum titer of Vitellogenin may aid in monitoring the sexual maturation of cod populations.

We also explore the cellular basis of pattern formation in oocytes of the cockroaches Blattella germanica and Periplaneta americana and the amphibian, Xenopus laevis with our studies of ion flux during early development. Our Ion Probe Facility is also being used to explore ionic factors surrounding the rapid growth of pollen tubes and root hair growth in conjunction with the Peter Hepler Lab which is a major force in this field of research.

The evolutionary consequences of pattern regulation are being studied in relation to tetrapod body plan and insect wing venation. Neutral aspects of wing venation are being used to measure phylogenetic and population differences among insects. The sexual dimorphism of Drosophila melanogaster wings is being used to study the genetic control of subtle morphology. The morphometrics of early fish development are being studied in the tautog, Tautoga onitis, and zebra fish, Brachydanio rerio in order to approach population and genetic aspects of morphological diversity.

Representative Publications

Kunkel J.G. and M.J. Jercinovic. (2013) Carbonate apatite formulation in cuticle structure adds resistance to microbial attack for American lobster. Marine Biology Research 9(1): 27-34. PDF

Kunkel J.G., W. Nagel and M.J. Jercinovic. (2012) Mineral Fine Structure of the American Lobster Cuticle. Journal of Shellfish Research 31(2): 515-526. PDF

McKenna S.T., J.G. Kunkel, M. Bosch, C.M. Rounds, L. Vidali, L.J. Winship, P.K. Hepler (2009) Exocytosis Precedes and Predicts the Increase in Growth in Oscillating Pollen Tubes. Plant Cell 21: 1-15. PDF

Marenzana, M., A.M. Shipley, P. Squitiero, J.G. Kunkel, A. Rubinacci. 2005. Bone as an ion exchange organ: evidence for instantaneous cell-dependent calcium efflux from bone not due to resorption. Bone, 37: 545-554. PDF

Kunkel, J.G., S. Cordeiro, Y(J) Xu, A.M. Shipley and J.A. Feijo. 2005. The use of non-invasive ion-selective microelectrode techniques for the study of plant development. Chapter V in Plant Electrophysiology- Theory and Methods ed. by AG Volkov, Springer-Verlag, Berlin/Heidelberg, pp 109-137. PDF

Zydlewski, J., S.D. McCormick and J.G. Kunkel. 2003. Late migration and seawater entry is physiologically disadvantageous for American shad juveniles. Journal of Fish Biology, 63: 1521-1537. PDF

Kunkel, J.G., L.-Y. Lin , Y. Xu, A.M.M. Prado, J.A. FeijÛ, P.P. Hwang and P.K. Hepler. 2001.  "The strategic use of Good buffers to measure proton gradients around growing pollen tubes".  In: Cell Biology of Plant and Fungal Tip Growth.  ed. by A. Geitmann, M. Cresti and I.B. Heath.  IOS Press, Amsterdam, pp 81-94. PDF

Hartling, R.C. and J.G. Kunkel. 1999. Developmental fate of the yolk protein lipovitellin in embryos and larvae of winter flounder, Pleuronectes americanus. J. Exp. Zool., 284: 686-95. PDF

Cardenas, L., Feijo, J.A., Kunkel, J.G., Sanchez, F., Holdaway-Clarke, T., Hepler, P.K., Quinto, C. 1999. Rhizobium nod factors induce increases in intracellular free calcium and extracellular calcium influxes in bean root hairs. Plant J., 19: 347-52. PDF

Feijo, J.A., J. Sainhas, G.R. Hackett, J.G. Kunkel and P.K. Hepler. 1999. Growing pollen tubes possess a constitutive alkaline band in the clear zone and a growth-dependent acidic tip. J. Cell Biol., 144(3): 483-496. PDF

Roy, S.J., Holdaway-Clarke, T.L., Hackett, G.R., Kunkel, J.G.., Lord, E.M., Hepler, P.K. 1999. Uncoupling secretion and tip growth in lily pollen tubes: evidence for the role of calcium in exocytosis. Plant J., 19: 379-386. PDF

Hartling, R.C., J.J. Pereira and J.G. Kunkel. 1997. Characterization of a heat-stable fraction of lipovitellin and development of an immunoassay for vitellogenin and yolk protein in winter flounder (Pleuronectes americanus) J. Exp. Zool., 278: 156-166. PDF

Iyengar, A.R. and J.G. Kunkel. 1995. Follicle cell calmodulin in Blattella germanica: Transcript accumulation during vitellogenesis is regulated by juvenile hormone. Developmental Biology, 170: 314-320. PDF

Kunkel, J.G. and E. Faszewski. 1995. Pattern of potassium ion and proton currents in the ovariole of the cockroach, Periplaneta americana, indicates future embryonic polarity. Biological Bulletin 189: 197-198. PDF

Zhang, Y. and J.G. Kunkel. 1994. Most egg calmodulin is a follicle cell contribution to the cytoplasm of the Blattella germanica oocyte. Developmental Biology, 161: 513-521. PDF

Kunkel, J.G. 1991. Models of pattern formation in insect oocytes. In Vivo, 5: 443-456. PDF