Kreiling Jill A.

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Last Name
Kreiling
First Name
Jill A.
ORCID
0000-0003-4440-2039

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  • Article
    The nerve hemoglobin of the bivalve mollusc Spisula solidissima : molecular cloning, ligand binding studies, and phylogenetic analysis
    (American Society for Biochemistry and Molecular Biology, 2005-12-13) Dewilde, Sylvia ; Ebner, Bettina ; Vinck, Evi ; Gilany, Kambiz ; Hankeln, Thomas ; Burmester, Thorsten ; Kreiling, Jill A. ; Reinisch, Carol L. ; Vanfleteren, Jacques R. ; Kiger, Laurent ; Marden, Michael C. ; Hundahl, Christian ; Fago, Angela ; Van Doorslaer, Sabine ; Moens, Luc
    Members of the hemoglobin (Hb) superfamily are present in nerve tissue of several vertebrate and invertebrate species. In vertebrates they display hexacoordinate heme iron atoms and are typically expressed at low levels (µM). Their function is still a matter of debate. In invertebrates they have a hexa- or pentacoordinate heme iron, are mostly expressed at high levels (mM), and have been suggested to have a myoglobin-like function. The native Hb of the surf clam, Spisula solidissima, composed of 162 amino acids, does not show specific deviations from the globin templates. UV-visible and resonance Raman spectroscopy demonstrate a hexacoordinate heme iron. Based on the sequence analogy, the histidine E7 is proposed as a sixth ligand. Kinetic and equilibrium measurements show a moderate oxygen affinity (P50 ~0.6 torr) and no cooperativity. The histidine binding affinity is 100-fold lower than in neuroglobin. Phylogenetic analysis demonstrates a clustering of the S. solidissima nerve Hb with mollusc Hbs and myoglobins, but not with the vertebrate neuroglobins. We conclude that invertebrate nerve Hbs expressed at high levels are, despite the hexacoordinate nature of their heme iron, not essentially different from other intracellular Hbs. They most likely fulfill a myoglobin-like function and enhance oxygen supply to the neurons
  • Article
    A New invertebrate member of the p53 gene family is developmentally expressed and responds to polychlorinated biphenyls
    (National Institute of Environmental Health Sciences, 2002-03-07) Jessen-Eller, Kathryn ; Kreiling, Jill A. ; Begley, Gail S. ; Steele, Marjorie E. ; Walker, Charles W. ; Stephens, Raymond E. ; Reinisch, Carol L.
    The cell-cycle checkpoint protein p53 both directs terminal differentiation and protects embryos from DNA damage. To study invertebrate p53 during early development, we identified three differentially expressed p53 family members (p53, p97, p120) in the surf clam, Spisula solidissima. In these mollusks, p53 and p97 occur in both embryonic and adult tissue, whereas p120 is exclusively embryonic. We sequenced, cloned, and characterized p120 cDNA. The predicted protein, p120, resembles p53 across all evolutionarily conserved regions and contains a C-terminal extension with a sterile alpha motif (SAM) as in p63 and p73. These vertebrate forms of p53 are required for normal inflammatory, epithelial, and neuronal development. Unlike clam p53 and p97, p120 mRNA and protein levels are temporally expressed in embryos, with mRNA levels decreasing with increasing p120 protein (R2 = 0.97). Highest surf clam p120 mRNA levels coincide with the onset of neuronal growth. In earlier work we have shown that neuronal development is altered by exposure to polychlorinated biphenyls (PCBs), a neurotoxic environmental contaminant. In this study we show that PCBs differentially affect expression of the three surf clam p53 family members. p120 mRNA and protein are reduced the most and earliest in development, p97 protein shows a smaller and later reduction, and p53 protein levels do not change. For the first time we report that unlike p53 and p97, p120 is specifically embryonic and expressed in a time-dependent manner. Furthermore, p120 responds to PCBs by 48 hr when PCB-induced suppression of the serotonergic nervous system occurs.