Growth-associated protein-43 is typically expressed at high levels in the nervous system during development. In adult animals, its expression is lower, but still observable in brain areas showing structural or functional plasticity. We examined patterns of GAP-43 immunoreactivity in the brain of the bullfrog, an animal whose nervous system undergoes considerable reorganization across metamorphic development and retains a strong capacity for plasticity in adulthood. Immunolabeling was mostly diffuse in hatchling tadpoles, but became progressively more discrete as larval development proceeded. In many brain areas, intensity of immunolabel peaked at metamorphic climax, the time of final transition from aquatic to semi-terrestrial life. Changes in intensity of GAP-43 expression in the medial vestibular nucleus, superior olivary nucleus, and torus semicircularis appeared correlated with stage-dependent functional changes in processing auditory stimuli. Immunolabeling in the Purkinje cell layer of the cerebellum and in the cerebellar nucleus was detectable at most developmental time points. Heavy immunolabel was present from early larval stages through the end of climax in the thalamus (ventromedial, anterior, posterior, central nuclei). Immunolabel in the tadpole telencephalon was observed around the lateral ventricles, and in the medial septum and ventral striatum. In postmetamorphic animals, immunoreactivity was confined mainly to the ventricular zones and immediately adjacent cell layers. GAP-43 expression was present in olfactory, auditory and optic cranial nerves throughout larval and postmetamorphic life. The continued expression of GAP-43 in brain nuclei and in cranial nerves throughout development and into adulthood reflects the high regenerative potential of the bullfrog’s central nervous system.

1.
Benowitz LI, Lewis ER (1983) Increased transport of 44,000- to 49,000-dalton acidic proteins during regeneration of the goldfish optic nerve: a two-dimensional gel analysis. J Neurosci 3:2153–2163.
2.
Benowitz LI, Routtenberg A (1997) GAP-43: an intrinsic determinant of neuronal development and plasticity. Trends Neurosci 20:84–91.
3.
Benowitz LI, Apostolides PJ, Perrone-Bizzozero N, Finklestein SP, Zwiers H (1988) Anatomical distribution of the growth-associated protein GAP-43/B-50 in the adult rat brain. J Neurosci 8:339–352.
4.
Benowitz LI, Perrone-Bizzozero NI, Neve RL, Rodriguez W (1990) GAP-43 as a marker for structural plasticity in the mature CNS. Prog Brain Res 86:309–320.
5.
Benowitz LI, Shashoua VE, Yoon MG (1981) Specific changes in rapidly transported proteins during regeneration of the goldfish optic nerve. J Neurosci 1:300–307.
6.
Boatright-Horowitz SS, Simmons AM (1997) Transient ‘deafness’ accompanies auditory development during metamorphosis from tadpole to frog. Proc Natl Acad Sci USA 94:14877–14882.
7.
Boatright-Horowitz SS, Garabedian CE, Odabashian KH, Simmons AM (1999) Coding of amplitude modulation in the auditory midbrain of the bullfrog across metamorphosis. J Comp Physiol A 184:219–231.
8.
Chaisuksunt V, Zhang Y, Anderson PN, Campbell G, Vaudano E, Schachner M, Lieberman AR (2000) Axonal regeneration from CNS neurons in the cerebellum and brainstem of adult rats: Correlation with the patterns of expression and distribution of messenger RNAs for L1, CHL1, c-jun and growth-associated protein-43. Neuroscience 100:87–108.
9.
Chapman JA, Weinstein JL, Simmons AM (2006) Cell proliferation in the Rana catesbeiana auditory medulla over metamorphic development. J Neurobiol 66:115–133.
10.
Currie J, Cowan WM (1975) The development of the retino-tectal projection in Rana pipiens. Dev Biol 46:103–119.
11.
Dani JW, Armstrong DM, Benowitz LI (1991) Mapping the development of the rat brain by GAP-43 immunocytochemistry. Neuroscience 40:277–287.
12.
Dent EW, Meiri KF (1998) Distribution of phosphorylated GAP-43 (neuromodulin) in growth cones directly reflects growth cone behavior. J Neurobiol 35:287–299.
13.
Denver RJ (1998) The molecular basis of thyroid hormone-dependent central nervous system remodeling during amphibian metamorphosis. Comp Biochem Physiol C Pharmacol Toxicol Endocrinol 119:219–228.
14.
Esdar C, Oehrlein SA, Reinhardt S, Maelicke A, Herget T (1999) The protein kinase C (PKC) substrate GAP-43 is already expressed in neural precursor cells, colocalizes with PKCη and binds calmodulin. Eur J Neurosci 11:503–516.
15.
Feig SL (2005) The differential distribution of the growth-associated protein-43 in first and higher order thalamic nuclei of the adult rat. Neuroscience 136:1147–1157.
16.
Ferrini M, Bisagno V, Piroli G, Grillo C, Deniselle MCG, DeNicola AF (2002) Effects of estrogen on choline-acetyltransferase immunoreactivity and GAP-43 mRNA in the forebrain of young and aging male rats. Cell Mol Neurobiol 22:289–301.
17.
Fritzsch B, Nikundiwe AM, Will U (1984) Projection patterns of lateral line afferents in anurans: A comparative HRP study. J Comp Neurol 229:451–469.
18.
Golding JP, Tonge DA (1993) Expression of GAP-43 in normal and regenerating nerves in the frog. Neuroscience 52:415–426.
19.
González A, López JM (2002) A forerunner of septohippocampal cholinergic system is present in amphibians. Neurosci Lett 327:111–114.
20.
Gosner KL (1960) A simplified table for staging anuran embryos and larvae with notes on identification. Herpetologica 16:183–190.
21.
Haas CA, Hollerach E, Deller T, Naumann T, Frotscher M (2000) Up-regulation of growth-associated protein 43 mRNA in rat medial septum neurons axotomized by fimbria-fornix transection. Eur J Neurosci 12:4233–4242.
22.
Haynes RL, Borenstein NA, Desilva TM, Folkerth RD, Liu LG, Volpe JJ, Kinney HC (2005) Axonal development in the cerebral white matter of the human fetus and infant. J Comp Neurol 484:156–167.
23.
Horowitz SS, Simmons AM (2007) Dynamic visualization of the developing nervous system of the bullfrog, Rana catesbeiana. Brain Res 1157:23–31.
24.
Horowitz SS, Chapman JA, Simmons AM (2007a) Plasticity of auditory medullary-midbrain connectivity across metamorphic development in the bullfrog, Rana catesbeiana. Brain Behav Evol 69:1–19.
25.
Horowitz SS, Tanyu LH, Simmons AM (2007b) Multiple mechanosensory modalities influence development of auditory function. J Neurosci 27:782–790.
26.
Horváth M, Forster CR, Illing RB (1997) Postnatal development of GAP-43 immunoreactivity in the auditory brainstem of the rat. J Comp Neurol 382:104–115.
27.
Hoskins SG (1986) Control of the development of the ipsilateral retinothalamic projection in Xenopus laevis by thyroxine: results and speculation. J Neurobiol 17:203–229.
28.
Illing RB, Cao QL, Forster CR, Laszig R (1999) Auditory brainstem: development and plasticity of GAP-43 mRNA expression in the rat. J Comp Neurol 412:353–372.
29.
Jacobson RD, Virág I, Skene JH (1986) A protein associated with axon growth, GAP-43, is widely distributed and developmentally regulated in rat CNS. J Neurosci 6:1843–1855.
30.
Kollros JJ, Thiesse ML (1988) Control of tectal cell number during larval development in Rana pipiens. J Comp Neurol 278:430–445.
31.
Kumaresan V, Kang C, Simmons AM (1998) Development and differentiation of the anuran auditory brainstem across metamorphosis: An acetylcholinesterase histochemical study. Brain Behav Evol 52:111–125.
32.
Marín O, González A, Smeets WJAJ (1997) Basal ganglia organization in amphibians: Efferent connections of the striatum and the nucleus accumbens. J Comp Neurol 380:23–50.
33.
McDiarmid RW, Altig R (1999) Research: materials and techniques. In: Tadpoles: the Biology of Anuran Larvae (McDiarmid RW, Altig R, eds), pp 7–23. Chicago, IL: University of Chicago Press.
34.
McGuire CB, Snipes GJ, Norden JJ (1988) Light-microscopic immunolocalization of the growth- and plasticity-associated protein GAP-43 in the developing rat brain. Dev Brain Res 41:277–291.
35.
Meiri KF, Pfenninger KH, Willard MB (1986) Growth-associated protein, GAP-43, a polypeptide that is induced when neurons extend axons, is a component of growth cones and corresponds to pp46, a major polypeptide of a subcellular fraction enriched in growth cones. Proc Natl Acad Sci USA 83:3537–3541.
36.
Neve RL, Finch EA, Bird ED, Benowitz LI (1988) Growth-associated protein GAP-43 is expressed selectively in associative regions of the adult human brain. Proc Natl Acad Sci USA 85:3638–3642.
37.
Nieuwenhuys R, Opdam P (1976) Structure of the brain stem. In: Frog Neurobiology (Llinas R, Precht W, eds), pp 81–855. New York:Springer-Verlag.
38.
Northcutt RG, Ronan M (1992) Afferent and efferent connections of the bullfrog medial pallium. Brain Behav Evol 40:1–16.
39.
Oestreicher AB, Gispen WH (1986) Comparison of the immunocytochemical distribution of the phosphoprotein B-50 in the cerebellum and hippocampus of immature and adult rat brain. Brain Res 375:267–279.
40.
Oestreicher AB, De Graan PN, Gispen WH, Verhaagen J, Schrama LH (1997) B-50, the growth associated protein-43: modulation of cell morphology and communication in the nervous system. Prog Neurobiol 53:627–686.
41.
Opdam R, Kemali M, Nieuwenhuys R (1976) Topological analysis of the brain stem of the frogs Rana esculenta and Rana catesbeiana. J Comp Neurol 165:307–332.
42.
Reh TA, Constantine-Paton M (1984) Retinal ganglion cell terminals change their projection sites during larval development of Rana pipiens. J Neurosci 4:442–457.
43.
Roden K, Endepols H, Walkowiak W (2005) Hodological characterization of the septum in anuran amphibians: I. Afferent connections. J Comp Neurol 483:415–436.
44.
Rodger J, Bartlett CA, Harman AM, Thomas C, Beazley LD, Dunlop SA (2001) Evidence that regenerating optic axons maintain long-term growth in the lizard Ctenophorus ornatus: growth-associated protein-43 and gefiltin expression. Neuroscience 102:647–654.
45.
Schrama LH, Lepperdinger G, Moritz A, van den Engel NK, Marquart A, Oestreicher AB, Eggen BJ, Hage WJ, Richter K, Destree OH (1997) B-50/growth-associated protein-43, a marker of neural development in Xenopus laevis. Neuroscience 76:635–652.
46.
Shi Y-B (1999) Amphibian Metamorphosis: From Morphology to Molecular Biology. New York: Wiley-Liss.
47.
Simmons AM, Horowitz SS (2007) Plasticity in the auditory system across metamorphosis. In: Hearing and Sound Communication in Amphibians (Fay RR, Popper AN, Narins PM, Feng AS, eds), pp 291–322. New York: Springer-Verlag.
48.
Simmons AM, Chapman JA, Brown RA (2006) Developmental changes in cell proliferation in the auditory midbrain of the bullfrog, Rana catesbeiana. J Neurobiol 66:1212–1224.
49.
Simmons AM, Horowitz SS, Brown RA (2008) Cell proliferation in the midbrain and forebrain of the adult frog, Rana catesbeiana. Brain Behav Evol 71:41–53.
50.
Skene JH (1989) Axonal growth–associated proteins. Ann Rev Neurosci 12:127–156.
51.
Skene JH, Willard M (1981) Changes in axonally transported proteins during axon regeneration in toad retinal ganglion cells. J Cell Biol 89:86–95.
52.
Skene JH, Jacobson RD, Snipes GJ, McGuire CB, Norden JJ, Freeman JA (1986) A protein induced during nerve growth (GAP-43) is a major component of growth-cone membranes. Science 233:783–786.
53.
Soto I, Marie B, Baro DJ, Blanco RE (2003) FGF-2 modulates expression and distribution of GAP-43 in frog retinal ganglion cells after optic nerve injury. J Neurosci Res 73:507–517.
54.
Van der Zee CE, Nielander HB, Vos JP, Lopes da Silva S, Verhaagen J, Oestreicher AB, Schrama LH, Schotman P, Gispen WH (1989) Expression of growth-associated protein B-50 (GAP43) in dorsal root ganglia and sciatic nerve during regenerative sprouting. J Neurosci 9:3505–3512.
55.
Westhoff G, Roth G, Straka H (2004) Topographic representation of vestibular and somatosensory signals in the anuran thalamus. Neuroscience 124:669–683.
56.
Wilczynski W, Northcutt RG (1983) Connections of the bullfrog striatum: Afferent organization. J Comp Neurol 214:321–332.
57.
Zakon HH, Capranica RR (1981) Reformation of organized connections in the auditory system after regeneration of the eighth nerve. Science 213:242–244.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.