@article{kulkarni_karavanich_atchley_anholt_2000, title={Characterization and differential expression of a human gene family of olfactomedin-related proteins}, volume={76}, ISSN={["0016-6723"]}, DOI={10.1017/S0016672300004584}, abstractNote={Olfactomedin-related proteins are secreted glycoproteins with conserved C-terminal motifs. Olfactomedin was originally identified as the major component of the mucus layer that surrounds the chemosensory dendrites of olfactory neurons. Homologues were subsequently found also in other tissues, including the brain and in species ranging from Caenorhabditis elegans to Homo sapiens. Most importantly, the TIGR/myocilin protein, expressed in the eye and associated with the pathogenesis of glaucoma, is an olfactomedin-related protein. The prevalence of olfactomedin-related proteins among species and their identification in different tissues prompted us to investigate whether a gene family exists within a species, specifically Homo sapiens. A GenBank search indeed revealed an entire human gene family of olfactomedin-related proteins with at least five members, designated hOlfA through hOlfD and the TIGR/myocilin protein. hOlfA corresponds to the rat neuronal AMZ protein. Phylogenetic analyses of 18 olfactomedin-related sequences resolved four distinct subfamilies. Among the human proteins, hOlfA and hOlfC, both expressed in brain, are most closely related. Northern blot analyses of 16 human tissues demonstrated highly specific expression patterns: hOlfA is expressed in brain, hOlfB in pancreas and prostate, hOlfC in cerebellum, hOlfD in colon, small intestine and prostate and TIGR/myocilin in heart and skeletal muscle. The link between TIGR/myocilin and ocular hypertension and the expression of several of these proteins in mucus-lined tissues suggest that they play an important role in regulating physical properties of the extracellular environment. Future studies can now assess whether other members of this gene family, like TIGR/myocilin, are also associated with human disease processes.}, number={1}, journal={GENETICAL RESEARCH}, author={Kulkarni, NH and Karavanich, CA and Atchley, WR and Anholt, RRH}, year={2000}, month={Aug}, pages={41–50} } @article{karavanich_atema_1998, title={Individual recognition and memory in lobster dominance}, volume={56}, ISSN={["1095-8282"]}, DOI={10.1006/anbe.1998.0914}, abstractNote={American lobsters, Homarus americanus, form stable dominance relationships in captivity. Size, sex and stage in the moult cycle are important determinants for dominance. Other factors, such as recent agonistic experience play a role. This paper investigates how lobsters maintain their stable dominance relationships: they may recognize individuals or alternatively, recognize overall dominance status. We paired lobsters in two consecutive 'boxing matches'. Results indicate that lobsters remember familiar opponents when kept either in isolation or in communal tanks for 24 h between their first and second fights. Subordinates immediately backed away from familiar dominants, avoiding a second fight. In some animals, this memory lasted between 1-2 weeks if pairs were kept separate between the first and second fights. When paired for the second fight against unfamiliar dominant lobsters, subordinate lobsters from first fights actively fought and won the encounter. These results suggest that lobsters are capable of 'individual recognition'. In nature, the observed social organization of lobsters may be maintained by individual recognition of a small number of residents inhabiting separate, nearby shelters. (c) 1998 The Association for the Study of Animal Behaviour.}, journal={ANIMAL BEHAVIOUR}, author={Karavanich, C and Atema, J}, year={1998}, month={Dec}, pages={1553–1560} } @article{karavanich_anholt_1998, title={Molecular evolution of olfactomedin}, volume={15}, ISSN={["0737-4038"]}, DOI={10.1093/oxfordjournals.molbev.a025975}, abstractNote={Olfactomedin is a secreted polymeric glycoprotein of unknown function, originally discovered at the mucociliary surface of the amphibian olfactory neuroepithelium and subsequently found throughout the mammalian brain. As a first step toward elucidating the function of olfactomedin, its phylogenetic history was examined to identify conserved structural motifs. Such conserved motifs may have functional significance and provide targets for future mutagenesis studies aimed at establishing the function of this protein. Previous studies revealed 33% amino acid sequence identity between rat and frog olfactomedins in their carboxyl terminal segments. Further analysis, however, reveals more extensive homologies throughout the molecule. Despite significant sequence divergence, cysteines essential for homopolymer formation such as the CXC motif near the amino terminus are conserved, as is the characteristic glycosylation pattern, suggesting that these posttranslational modifications are essential for function. Furthermore, evolutionary analysis of a region of 53 amino acids of fish, frog, rat, mouse, and human olfactomedins indicates that an ancestral olfactomedin gene arose before the evolution of terrestrial vertebrates and evolved independently in teleost, amphibian, and mammalian lineages. Indeed, a distant olfactomedin homolog was identified in Caenorhabditis elegans. Although the amino acid sequence of this invertebrate protein is longer and highly divergent compared with its vertebrate homologs, the protein from C. elegans shows remarkable similarities in terms of conserved motifs and posttranslational modification sites. Six universally conserved motifs were identified, and five of these are clustered in the carboxyl terminal half of the protein. Sequence comparisons indicate that evolution of the N-terminal half of the molecule involved extensive insertions and deletions; the C-terminal segment evolved mostly through point mutations, at least during vertebrate evolution. The widespread occurrence of olfactomedin among vertebrates and invertebrates underscores the notion that this protein has a function of universal importance. Furthermore, extensive modification of its N-terminal half and the acquisition of a C-terminal SDEL endoplasmic-reticulum-targeting sequence may have enabled olfactomedin to adopt new functions in the mammalian central nervous system.}, number={6}, journal={MOLECULAR BIOLOGY AND EVOLUTION}, author={Karavanich, CA and Anholt, RRH}, year={1998}, month={Jun}, pages={718–726} } @inbook{karavanich_anholt_1998, title={Olf evolution of olfactomedin: Structural constraints and conservation of primary sequence motifs}, volume={855}, booktitle={Olfaction and taste XII: An international symposium}, publisher={New York, NY: New York Academy of Sciences}, author={Karavanich, C. A. and Anholt, R. R. H.}, year={1998}, pages={294–300} } @article{karavanich_atema_1998, title={Olfactory recognition of urine signals in dominance fights between male lobster, Homarus americanus}, volume={135}, ISSN={["0005-7959"]}, DOI={10.1163/156853998792640440}, abstractNote={ Abstract The maintenance of dominance hierarchies in the American lobster (Homarus americanus) is based on recognition of the dominant animal by the loser of a recent fight. It is hypothesized that chemical signals are the basis of this recognition. Adult male lobsters were paired for initial boxing matches between unfamiliar animals. The same pairs were re-matched for 3 more consecutive fights. In the first experiment, treatment animals had their primary olfactory receptor cells of the lateral and medial antennules lesioned before fights 2-4 and control animals received sham lesions. The durations of fights 2-4 for control pairs were significantly shorter than the durations of fights between lesioned animals. In the second experiment, male pairs were again allowed to establish a dominance relationship in a first fight. During second fights, urine release by both animals was prevented by the use of catheters in treatment animals while control pairs wore sham catheters. Again, durations of the second fights of control animals were significantly shorter than those of treatment animals. Together, these experiments indicate that urine-carried chemical signals, perceived by the antennules, reduce the duration and aggression of male dominance fights on subsequent days because the loser of the first fight backs off almost immediately when he smells the urine of the known dominant. }, journal={BEHAVIOUR}, author={Karavanich, C and Atema, J}, year={1998}, month={Aug}, pages={719–730} }