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Impact of experience-dependent and -independent factors on gene expression in songbird brain. Proc Natl Acad Sci U S A 2012; 109 Suppl 2:17245-52. [PMID: 23045667 DOI: 10.1073/pnas.1200655109] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Songbirds provide rich natural models for studying the relationships between brain anatomy, behavior, environmental signals, and gene expression. Under the Songbird Neurogenomics Initiative, investigators from 11 laboratories collected brain samples from six species of songbird under a range of experimental conditions, and 488 of these samples were analyzed systematically for gene expression by microarray. ANOVA was used to test 32 planned contrasts in the data, revealing the relative impact of different factors. The brain region from which tissue was taken had the greatest influence on gene expression profile, affecting the majority of signals measured by 18,848 cDNA spots on the microarray. Social and environmental manipulations had a highly variable impact, interpreted here as a manifestation of paradoxical "constitutive plasticity" (fewer inducible genes) during periods of enhanced behavioral responsiveness. Several specific genes were identified that may be important in the evolution of linkages between environmental signals and behavior. The data were also analyzed using weighted gene coexpression network analysis, followed by gene ontology analysis. This revealed modules of coexpressed genes that are also enriched for specific functional annotations, such as "ribosome" (expressed more highly in juvenile brain) and "dopamine metabolic process" (expressed more highly in striatal song control nucleus area X). These results underscore the complexity of influences on neural gene expression and provide a resource for studying how these influences are integrated during natural experience.
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White SA. Genes and vocal learning. BRAIN AND LANGUAGE 2010; 115:21-28. [PMID: 19913899 PMCID: PMC2888939 DOI: 10.1016/j.bandl.2009.10.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Revised: 09/25/2009] [Accepted: 10/12/2009] [Indexed: 05/28/2023]
Abstract
Could a mutation in a single gene be the evolutionary lynchpin supporting the development of human language? A rare mutation in the molecule known as FOXP2 discovered in a human family seemed to suggest so, and its sequence phylogeny reinforced a Chomskian view that language emerged wholesale in humans. Spurred by this discovery, research in primates, rodents and birds suggests that FoxP2 and other language-related genes are interactors in the neuromolecular networks that underlie subsystems of language, such symbolic understanding, vocal learning and theory of mind. The whole picture will only come together through comparative and integrative study into how the human language singularity evolved.
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Affiliation(s)
- Stephanie A White
- Department of Physiological Science, University of California, Los Angeles, 90095, USA.
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Thode C, Güttinger HR, Darlison MG. Expression of the GABA(A) receptor gamma4-subunit gene in discrete nuclei within the zebra finch song system. Neuroscience 2008; 157:143-52. [PMID: 18824085 DOI: 10.1016/j.neuroscience.2008.08.057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 08/29/2008] [Accepted: 08/29/2008] [Indexed: 11/26/2022]
Abstract
The acquisition, production and maintenance of song by oscine birds is a form of audition-dependent learning that, in many ways, resembles the process by which humans learn to speak. In songbirds, the generation of structured song is determined by the activity of two interconnected neuronal pathways (the anterior forebrain pathway and the vocal motor pathway), each of which contains a number of discrete nuclei that together form the song system. It is becoming increasingly evident that inhibitory GABAergic mechanisms are indispensable in counterbalancing the excitatory actions of glutamate and, thus, likely shape the neuronal firing patterns of neurons within this network. Furthermore, there is compelling evidence for the involvement of GABA(A) receptors, although the molecular composition of these has, to date, remained elusive. Here we describe the isolation of a complementary DNA for the zebra finch GABA(A) receptor gamma4 subunit, and map the expression pattern of the corresponding gene within the zebra finch (Taeniopygia guttata) brain. Our findings show, remarkably, that the gamma4-subunit transcript is highly enriched in the major nuclei of the song system, including the lateral magnocellular nucleus of the anterior nidopallium (LMAN), the medial magnocellular nucleus of the anterior nidopallium (MMAN), Area X, the robust nucleus of the arcopallium (RA) and the HVC (used as the proper name), as well as Field L, which innervates the area surrounding HVC. In summary, we have demonstrated the presence of the mRNA for the gamma4 subunit of the GABA(A) receptor, the major inhibitory receptor in brain, in most of the nuclei of the two neural circuits that mediate song production in the zebra finch. This not only marks the beginning of the characterization of the GABA(A) receptor subtype(s) that mediates the actions of GABA in the song system but it also provides a robust molecular marker with which to distinguish song system-specific brain structures.
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Affiliation(s)
- C Thode
- Neuroscience and Signal Transduction Laboratory, School of Science and Technology, College of Science, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, UK.
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Matsunaga E, Okanoya K. Expression analysis of cadherins in the songbird brain: relationship to vocal system development. J Comp Neurol 2008; 508:329-42. [PMID: 18322922 DOI: 10.1002/cne.21676] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Songbirds learn their songs as juveniles. The brains of songbirds have a series of nuclei and neural circuits called the song system, which is indispensable for vocal learning and production. In the present study we analyzed the expression patterns of cell adhesion molecules, cadherins, in the Bengalese finch (Lonchura striata var. domestica) to investigate their potential involvement in song nuclei and neural circuit formation. We found that cadherin-6B was expressed in many song nuclei of the juvenile and adult brain, while R-cadherin was complementarily expressed in surrounding areas. On the other hand, cadherin-7 was expressed in the robust nucleus of the arcopallium (RA) in the sensory learning stage, and its expression was downregulated during the sensorimotor learning stage. This downregulation of cadherin-7 was sexually dimorphic, suggesting its involvement in song development. Other cadherins, including cadherin-9, -10, and -12, showed different song-nuclei-related expression profiles. These patterns of song nuclei related expression suggest the possibility that cadherins are involved in the formation and maintenance of the song nuclei or neural pathways of the song system.
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Affiliation(s)
- Eiji Matsunaga
- Laboratory for Biolinguistics, RIKEN Brain Science Institute, Wako, Japan.
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VELHO TARCISOA, LOVELL PETER, MELLO CLAUDIOV. Enriched expression and developmental regulation of the middle-weight neurofilament (NF-M) gene in song control nuclei of the zebra finch. J Comp Neurol 2007; 500:477-97. [PMID: 17120287 PMCID: PMC4032091 DOI: 10.1002/cne.21180] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Songbirds evolved a complex set of dimorphic telencephalic nuclei that are essential for the learning and production of song. These nuclei, which together make up the oscine song control system, present several neurochemical properties that distinguish them from the rest of the telencephalon. Here we show that the expression of the gene encoding the middle-weight neurofilament (NF-M), an important component of the neuronal cytoskeleton and a useful tool for studying the cytarchitectonic organization of mammalian cortical areas, is highly enriched in large neurons within pallial song control nuclei (nucleus HVC, robustus nucleus of the arcopallium, and lateral magnocellular nucleus of the nidopallium) of male zebra finches (Taeniopygia guttata). We also show that this transcript is highly expressed in large neurons in the medulla, pons, midbrain, and thalamus. Moreover, we demonstrate that NF-M expression in song control nuclei changes during postembryonic development, peaking during an early phase of the song-learning period that coincides with the maturation of the song system. We did not observe changes in NF-M expression in auditory areas or in song control nuclei in the contexts of hearing song or singing, although these contexts result in marked induction of the transcription factor ZENK. This observation suggests that NF-M might not be under the regulatory control of ZENK in auditory areas or in song control nuclei. Overall, our data indicate that NF-M is a neurochemical marker for pallial song control nuclei and provide suggestive evidence of an involvement of NF-M in the development and/or maturation of the oscine song control system.
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Affiliation(s)
| | | | - CLAUDIO V. MELLO
- Correspondence to: Claudio V. Mello, MD, PhD, Neurological Sciences Institute, Oregon Health and Science University, 505 NW 185th Ave., Beaverton, OR 97006.
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Gahr M. Sexual Differentiation of the Vocal Control System of Birds. GENETICS OF SEXUAL DIFFERENTIATION AND SEXUALLY DIMORPHIC BEHAVIORS 2007; 59:67-105. [PMID: 17888795 DOI: 10.1016/s0065-2660(07)59003-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Birds evolved neural circuits of various complexities in relation to their capacity to produce learned or unlearned vocalizations. These vocalizations, in particular those that function in the realm of reproduction, are frequently sexually dimorphic, both in vocal learners (songbirds, parrots, some hummingbirds) and vocal nonlearners (all other birds). In many cases, the development and/or the adult differentiation of vocalizations of sociosexual function is sensitive to sex hormones, androgens and estrogens. The underlying mechanisms have been studied in detail in songbirds, a bird group that comprises about half of all bird species. Next to unlearned calls, songbirds produce learned songs that require forebrain vocal control areas that express receptors for androgens and estrogens. These forebrain vocal areas are sexually dimorphic in many species, but a clear relation between the degree of "brain sex" and sex differences in vocal pattern is lacking, except that a minimum number of vocal neurons is necessary to sing learned songs. Genetic brain-intrinsic mechanisms are likely to determine the neuron pools that develop into forebrain song control areas. Subsequently, gonadal steroid hormones, androgens and estrogens, modulate the fate of these neurons and thus the functionality of the vocal control systems. Further action of gonadal hormones, and may be other factors signaling the sociosexual and physical environment, affect the phenotype of vocal control areas in adulthood. Despite the clear evidence of hormone dependency of both adult vocalizations and phenotypes of vocal neuron pools, their causal relation is little understood.
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Affiliation(s)
- Manfred Gahr
- Max Planck Institute for Ornithology, Seewiesen, Germany
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WADA KAZUHIRO, SAKAGUCHI HIRONOBU, JARVIS ERICHD, HAGIWARA MASATOSHI. Differential expression of glutamate receptors in avian neural pathways for learned vocalization. J Comp Neurol 2004; 476:44-64. [PMID: 15236466 PMCID: PMC2517240 DOI: 10.1002/cne.20201] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Learned vocalization, the substrate for human language, is a rare trait. It is found in three distantly related groups of birds-parrots, hummingbirds, and songbirds. These three groups contain cerebral vocal nuclei for learned vocalization not found in their more closely related vocal nonlearning relatives. Here, we cloned 21 receptor subunits/subtypes of all four glutamate receptor families (AMPA, kainate, NMDA, and metabotropic) and examined their expression in vocal nuclei of songbirds. We also examined expression of a subset of these receptors in vocal nuclei of hummingbirds and parrots, as well as in the brains of dove species as examples of close vocal nonlearning relatives. Among the 21 subunits/subtypes, 19 showed higher and/or lower prominent differential expression in songbird vocal nuclei relative to the surrounding brain subdivisions in which the vocal nuclei are located. This included relatively lower levels of all four AMPA subunits in lMAN, strikingly higher levels of the kainite subunit GluR5 in the robust nucleus of the arcopallium (RA), higher and lower levels respectively of the NMDA subunits NR2A and NR2B in most vocal nuclei and lower levels of the metabotropic group I subtypes (mGluR1 and -5) in most vocal nuclei and the group II subtype (mGluR2), showing a unique expression pattern of very low levels in RA and very high levels in HVC. The splice variants of AMPA subunits showed further differential expression in vocal nuclei. Some of the receptor subunits/subtypes also showed differential expression in hummingbird and parrot vocal nuclei. The magnitude of differential expression in vocal nuclei of all three vocal learners was unique compared with the smaller magnitude of differences found for nonvocal areas of vocal learners and vocal nonlearners. Our results suggest that evolution of vocal learning was accompanied by differential expression of a conserved gene family for synaptic transmission and plasticity in vocal nuclei. They also suggest that neural activity and signal transduction in vocal nuclei of vocal learners will be different relative to the surrounding brain areas.
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MESH Headings
- Alternative Splicing/genetics
- Animals
- Birds/anatomy & histology
- Birds/growth & development
- Birds/metabolism
- Brain/cytology
- Brain/growth & development
- Brain/metabolism
- Cell Differentiation/genetics
- Gene Expression Regulation, Developmental/genetics
- Learning/physiology
- Male
- Neural Pathways/cytology
- Neural Pathways/growth & development
- Neural Pathways/metabolism
- Neuronal Plasticity/genetics
- Parrots/anatomy & histology
- Parrots/growth & development
- Parrots/metabolism
- Phylogeny
- Protein Subunits/genetics
- Protein Subunits/metabolism
- RNA, Messenger/metabolism
- Receptors, AMPA/genetics
- Receptors, AMPA/metabolism
- Receptors, Glutamate/metabolism
- Receptors, Kainic Acid/genetics
- Receptors, Kainic Acid/metabolism
- Receptors, Metabotropic Glutamate/genetics
- Receptors, Metabotropic Glutamate/metabolism
- Receptors, N-Methyl-D-Aspartate/genetics
- Receptors, N-Methyl-D-Aspartate/metabolism
- Songbirds/anatomy & histology
- Songbirds/growth & development
- Songbirds/metabolism
- Synaptic Transmission/genetics
- Telencephalon/cytology
- Telencephalon/growth & development
- Telencephalon/metabolism
- Vocalization, Animal/physiology
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Affiliation(s)
- KAZUHIRO WADA
- Department of Neurobiology, Duke University Medical Center, Durham, North Carolina 27710
- Department of Functional Genomics, Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8519, Japan
- Correspondence to: Erich D. Jarvis and/or Kazuhiro Wada Department of Neurobiology, Box 3209, Duke University Medical Center, Durham, NC 27710. E-mail: and/or
| | - HIRONOBU SAKAGUCHI
- Department of Physiology, Dokkyou University, School of Medicine, Mibu, Tochigi 321-0293, Japan
| | - ERICH D. JARVIS
- Department of Neurobiology, Duke University Medical Center, Durham, North Carolina 27710
- Correspondence to: Erich D. Jarvis and/or Kazuhiro Wada Department of Neurobiology, Box 3209, Duke University Medical Center, Durham, NC 27710. E-mail: and/or
| | - MASATOSHI HAGIWARA
- Department of Functional Genomics, Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8519, Japan
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Abstract
Vocal learning is a rare trait. Humans depend on vocal learning to acquire spoken language, but most species that communicate acoustically have an innate repertoire of sounds that they use for information exchange. Among the few non-human species that also rely on vocal learning, songbirds have provided by far the most information for understanding this process. This article concentrates on the genetic components of vocal learning in humans and birds. We summarize the existing evidence for a genetic predisposition towards acquiring the species-specific human and avian vocal repertoires. We describe the approaches used for finding genes involved in shaping the neural circuitry required for vocal learning or in mediating the learning process itself. Special attention is given to a particular gene, FOXP2, which has been implicated in a human speech and language disorder. We have studied FoxP2 in avian vocal learners and non-learners and review evidence that links both the molecule and its close homologue FoxP1 to the development of brain regions implicated in vocal learning and to their function. FoxP2 has a characteristic expression pattern in a brain structure uniquely associated with learned vocal communication, Area X in songbirds, or its analogue in parrots and hummingbirds. In both avian song learners and non-learners FoxP2 expression predominates in sensory and sensory-motor circuits. These latter regions also express FoxP2 in mammals and reptiles. We conclude that FoxP2 is important for the building and function of brain pathways including, but not limited to, those essential for learned vocal communication.
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Affiliation(s)
- Constance Scharff
- Max Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany.
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Teramitsu I, Kudo LC, London SE, Geschwind DH, White SA. Parallel FoxP1 and FoxP2 expression in songbird and human brain predicts functional interaction. J Neurosci 2004; 24:3152-63. [PMID: 15056695 PMCID: PMC6730014 DOI: 10.1523/jneurosci.5589-03.2004] [Citation(s) in RCA: 253] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Humans and songbirds are two of the rare animal groups that modify their innate vocalizations. The identification of FOXP2 as the monogenetic locus of a human speech disorder exhibited by members of the family referred to as KE enables the first examination of whether molecular mechanisms for vocal learning are shared between humans and songbirds. Here, in situ hybridization analyses for FoxP1 and FoxP2 in a songbird reveal a corticostriatal expression pattern congruent with the abnormalities in brain structures of affected KE family members. The overlap in FoxP1 and FoxP2 expression observed in the songbird suggests that combinatorial regulation by these molecules during neural development and within vocal control structures may occur. In support of this idea, we find that FOXP1 and FOXP2 expression patterns in human fetal brain are strikingly similar to those in the songbird, including localization to subcortical structures that function in sensorimotor integration and the control of skilled, coordinated movement. The specific colocalization of FoxP1 and FoxP2 found in several structures in the bird and human brain predicts that mutations in FOXP1 could also be related to speech disorders.
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Affiliation(s)
- Ikuko Teramitsu
- Interdepartmental Programs in Molecular, Cellular, and Integrative Physiology, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
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10
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Abstract
The biology of songbirds poses fundamental questions about the interplay between gene, brain, and behavior. New tools of genomic analysis will be invaluable in pursuing answers to these questions. This review begins with a summary of the broad properties of the songbird genome and how songbird brain gene expression has been measured in past studies. Four key problems in songbird biology are then considered from a genomics perspective: What role does differential gene expression play in the development, maintenance, and functional organization of the song control circuit? Does gene regulation set boundaries on the process of juvenile song learning? What is the purpose of song-induced gene activity in the adult brain? How does the genome underlie the profound sexual differentiation of the song control circuit? Finally, the range of genomic technologies currently or soon to be available to songbird researchers is briefly reviewed. These technologies include online databases of expressed genes ("expressed sequence tags" or ESTs); a complete library of the zebra finch genome maintained as a bacterial artificial chromosome (BAC) library; DNA microarrays for simultaneous measurement of many genes in a single experiment; and techniques for gene manipulation in the organism. Collectively, these questions and techniques define the field of songbird neurogenomics.
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Affiliation(s)
- David F Clayton
- Cell & Structural Biology, Neuroscience and Bioengineering, Beckman Institute, University of Illinois, Urbana, IL 61801, USA.
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Gahr M. Hormone-Dependent Neural Plasticity in the Juvenile and Adult Song System: What Makes a Successful Male? Ann N Y Acad Sci 2004; 1016:684-703. [PMID: 15313800 DOI: 10.1196/annals.1298.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The sexual quality of adult song is the result of genetic and epigenetic mechanisms shaping the neural song system throughout life. Genetic brain-intrinsic mechanisms determine the neuron pools that develop into forebrain song control areas independent of gonadal steroid hormones, androgens and estrogens. One fate of these neurons is the potential to express sex steroid receptors, such as androgen and estrogen receptors. Genetic brain-intrinsic mechanisms, too, determine the activity of hypothalamic-pituitary-gonad (HPG) axis, i.e., the working range and responsiveness of HPG axis to produce gonadal hormones. The epigenetic action of gonadal steroid hormones (androgens and estrogens) on determined vocal neurons is required to maintain and increase the pool of determined vocal neurons and to complete the connections of the vocal system, i.e., to make it function motorically. The subsequent influence of environmental information, including both external (socio-sexual and physical) and internal (body physiology) signals, specify the further neural phenotype of vocal areas either through acting on the HPG axis and differential release of gonadal hormones or through non-gonadal hormone systems, both of which have target neurons in the functional vocal system. Despite the clear evidence of hormone dependency of the development of both the adult song phenotype and song system phenotype, their causal relation is complex.
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Affiliation(s)
- Manfred Gahr
- Department of Developmental and Behavioural Neuroscience, Institute of Neuroscience, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, 1087 De Boelelaan, 1081 HV Amsterdam, The Netherlands.
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12
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Abstract
In mammals and birds, the sex of the brain has been attributed to the action of gonadal hormones. In males, testosterone from the testes acts early in life to make the brain masculine. Studies of songbirds and rodents suggest, however, that male and female brain cells are intrinsically different also because of the sex differences in the expression of sex chromosome genes within the cells.
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Affiliation(s)
- Arthur P Arnold
- Department of Physiological Science, UCLA, 621 Charles E. Young Drive South, Room 4117, Los Angeles CA 90095-1606, USA.
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The Evolution of Central Pathways and Their Neural Processing Patterns. EVOLUTION OF THE VERTEBRATE AUDITORY SYSTEM 2004. [DOI: 10.1007/978-1-4419-8957-4_10] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Zijlstra A, Testa JE, Quigley JP. Targeting the proteome/epitome, implementation of subtractive immunization. Biochem Biophys Res Commun 2003; 303:733-44. [PMID: 12670472 DOI: 10.1016/s0006-291x(03)00357-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Monoclonal antibody technology has generated invaluable tools for both the analytical and clinical sciences. However, standard immunization approaches frequently fail to provide monoclonal antibodies with the desired specificity. Subtractive immunization provides a powerful alternative to standard immunization and allows for the production of truly unique antibodies. With the intent of targeting specific epitopes within the proteome, subtractive immunization has been broadly and successfully implemented for the production of monoclonal antibodies otherwise unobtainable by standard immunization. Subtractive immunization utilizes a distinct immune tolerization approach that can substantially enhance the generation of monoclonal antibodies to desired antigens. The approach is based on tolerizing the host animal to immunodominant or otherwise undesired antigen(s) (tolerogen) that may be structurally or functionally related to the antigen of interest. Tolerization of the host animal can be achieved through one of three methods: High Zone, Neonatal, or Drug-induced tolerization. The tolerized animal is then inoculated with the desired antigen (immunogen) and antibodies generated by the subsequent immune response are screened for the desired antigenic reactivity. Over the past 15 years a large number of investigators have used the subtractive approach with cleverly chosen tolerogen-immunogen combinations and successfully generated uniquely reactive antibodies which are often neutralizing or function-blocking. This review will focus on the implementation of subtractive immunization for the production of antibodies otherwise unobtainable by standard immunization.
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Affiliation(s)
- Andries Zijlstra
- Division of Vascular Biology, Department of Cell Biology, The Scripps Research Institute, 10550 N. Torrey Pine Road, La Jolla, CA, USA
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15
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Kelley DB. Is song special? Neuron 2001; 31:508-10. [PMID: 11545707 DOI: 10.1016/s0896-6273(01)00399-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Akutagawa and Konishi (2001)([this issue of Neuron]) describe the spatial and temporal pattern of SNAg (song system nuclear antigen) expression within a subset of song-associated forebrain nuclei of grass finches. The timing and estrogen inducibility of SNAg expression suggest that it may function in establishing neural connections key to vocal learning.
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Affiliation(s)
- D B Kelley
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
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