The extracellular matrix glycoprotein tenascin-R affects adult but not developmental neurogenesis in the olfactory bulb

TY - JOUR

T1 - The extracellular matrix glycoprotein tenascin-R affects adult but not developmental neurogenesis in the olfactory bulb

AU - David, Linda Suzanne

AU - Schachner, Melitta

AU - Saghatelyan, Armen

PY - 2013/6/19

Y1 - 2013/6/19

N2 - Neuronal precursors produced in the subventricular zone throughout an animal's life migrate tangentially along the rostral migratory stream and, once in the olfactory bulb (OB), turn to migrate radially to the bulbar layers, where they differentiate into interneurons. Despite extensive investigations, it has remained largely unknown whether the same molecular mechanisms control OB neurogenesis during early postnatal development and in adulthood. In this study, we show that the extracellular matrix glycoprotein tenascin-R (TNR) is produced in the granule cell layer of the OB and that its expression increases during postnatal development. Time-lapse video imaging and morphological analyses revealed that a lack of TNR decreases the radial migration of neuronal precursors in the adult, but not in the developing OB. A lack of TNR also reduces spine development of newborn neurons in adult mice. To understand the functional consequences of a lack of TNR, we performed electrophysiological and behavioral studies on young and adult mice. Electrophysiological recordings showed that mitral cells, the target cells of newly generated interneurons, receive reduced spontaneous and evoked inhibitory activity in adult, but not young, TNR knock-out mice. Moreover, the synchronized activity of mitral cells was decreased in the OB of adult TNR knock-out mice. Behavioral studies revealed that the lower numbers of newborn interneurons in the adult OB induce alterations in short-term odor memory. Our results indicate that TNR modulates adult but not developmental neurogenesis in the OB and also highlight that the regulation of OB neurogenesis can vary during an animal's lifetime.

AB - Neuronal precursors produced in the subventricular zone throughout an animal's life migrate tangentially along the rostral migratory stream and, once in the olfactory bulb (OB), turn to migrate radially to the bulbar layers, where they differentiate into interneurons. Despite extensive investigations, it has remained largely unknown whether the same molecular mechanisms control OB neurogenesis during early postnatal development and in adulthood. In this study, we show that the extracellular matrix glycoprotein tenascin-R (TNR) is produced in the granule cell layer of the OB and that its expression increases during postnatal development. Time-lapse video imaging and morphological analyses revealed that a lack of TNR decreases the radial migration of neuronal precursors in the adult, but not in the developing OB. A lack of TNR also reduces spine development of newborn neurons in adult mice. To understand the functional consequences of a lack of TNR, we performed electrophysiological and behavioral studies on young and adult mice. Electrophysiological recordings showed that mitral cells, the target cells of newly generated interneurons, receive reduced spontaneous and evoked inhibitory activity in adult, but not young, TNR knock-out mice. Moreover, the synchronized activity of mitral cells was decreased in the OB of adult TNR knock-out mice. Behavioral studies revealed that the lower numbers of newborn interneurons in the adult OB induce alterations in short-term odor memory. Our results indicate that TNR modulates adult but not developmental neurogenesis in the OB and also highlight that the regulation of OB neurogenesis can vary during an animal's lifetime.

KW - Aging

KW - Algorithms

KW - Animals

KW - Antimetabolites

KW - Behavior, Animal

KW - Blotting, Western

KW - Bromodeoxyuridine

KW - Cell Movement

KW - Dendrites

KW - Immunohistochemistry

KW - Male

KW - Membrane Potentials

KW - Memory, Short-Term

KW - Mice

KW - Mice, Inbred C57BL

KW - Mice, Knockout

KW - Neurogenesis

KW - Olfactory Bulb

KW - Patch-Clamp Techniques

KW - Sensory Thresholds

KW - Smell

KW - Stereotaxic Techniques

KW - Tenascin

U2 - 10.1523/JNEUROSCI.5728-12.2013

DO - 10.1523/JNEUROSCI.5728-12.2013

M3 - SCORING: Journal article

C2 - 23785146

VL - 33

SP - 10324

EP - 10339

JO - J NEUROSCI

JF - J NEUROSCI

SN - 0270-6474

IS - 25

ER -