Dynamic FoxG1 Expression Coordinates the Integration of Multipolar Pyramidal Neuron Precursors into the Cortical Plate

Neuron

Volumn 74, Issue 6, 2012, Pages 1045-1058

  Miyoshi, Goichi ^a   Fishell, Gord ^a  

^a NEW YORK UNIVERSITY SCHOOL OF MEDICINE   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

NERVE PROTEIN; PROTEIN FOXG1; PROTEIN UNC5D; TRANSCRIPTION FACTOR; UNCLASSIFIED DRUG;

ANIMAL CELL; ARTICLE; BRAIN CORTEX; CELL CYCLE PHASE; CELL MIGRATION; CONTROLLED STUDY; DOWN REGULATION; MOLECULAR DYNAMICS; NEURAL STEM CELL; NONHUMAN; PHASE TRANSITION; PRIORITY JOURNAL; PROTEIN ASSEMBLY; PROTEIN EXPRESSION; PYRAMIDAL NERVE CELL; TRANSCRIPTION REGULATION;

ANIMALS; CELL MOVEMENT; CEREBRAL CORTEX; FORKHEAD TRANSCRIPTION FACTORS; GENE EXPRESSION REGULATION, DEVELOPMENTAL; MICE; NERVE TISSUE PROTEINS; PYRAMIDAL CELLS;

EID: 84862689222     PISSN: 08966273     EISSN: 10974199     Source Type: Journal    
DOI: 10.1016/j.neuron.2012.04.025     Document Type: Article

References (100)

1. Ackerman S.L., Kozak L.P., Przyborski S.A., Rund L.A., Boyer B.B., Knowles B.B. The mouse rostral cerebellar malformation gene encodes an UNC-5-like protein. Nature 1997, 386:838-842.
2. Alcántara S., Ruiz M., De Castro F., Soriano E., Sotelo C. Netrin 1 acts as an attractive or as a repulsive cue for distinct migrating neurons during the development of the cerebellar system. Development 2000, 127:1359-1372.
3. Alfano C., Viola L., Heng J.I., Pirozzi M., Clarkson M., Flore G., De Maio A., Schedl A., Guillemot F., Studer M. COUP-TFI promotes radial migration and proper morphology of callosal projection neurons by repressing Rnd2 expression. Development 2011, 138:4685-4697.
4. Angevine J.B.J., Sidman R.L. Autoradiographic study of cell migration during histogenesis of cerebral cortex in the mouse. Nature 1961, 192:766-768.
5. Ariani F., Hayek G., Rondinella D., Artuso R., Mencarelli M.A., Spanhol-Rosseto A., Pollazzon M., Buoni S., Spiga O., Ricciardi S., et al. FOXG1 is responsible for the congenital variant of Rett syndrome. Am. J. Hum. Genet. 2008, 83:89-93.
6. Arnold S.J., Huang G.J., Cheung A.F., Era T., Nishikawa S., Bikoff E.K., Molnár Z., Robertson E.J., Groszer M. The T-box transcription factor Eomes/Tbr2 regulates neurogenesis in the cortical subventricular zone. Genes Dev. 2008, 22:2479-2484.
7. Barnes A.P., Lilley B.N., Pan Y.A., Plummer L.J., Powell A.W., Raines A.N., Sanes J.R., Polleux F. LKB1 and SAD kinases define a pathway required for the polarization of cortical neurons. Cell 2007, 129:549-563.
8. Barnes A.P., Solecki D., Polleux F. New insights into the molecular mechanisms specifying neuronal polarity in vivo. Curr. Opin. Neurobiol. 2008, 18:44-52.
9. Bertrand N., Castro D.S., Guillemot F. Proneural genes and the specification of neural cell types. Nat. Rev. Neurosci. 2002, 3:517-530.
10. Bock H.H., Herz J. Reelin activates SRC family tyrosine kinases in neurons. Curr. Biol. 2003, 13:18-26.
11. Britanova O., Alifragis P., Junek S., Jones K., Gruss P., Tarabykin V. A novel mode of tangential migration of cortical projection neurons. Dev. Biol. 2006, 298:299-311.
12. Brunetti-Pierri N., Paciorkowski A.R., Ciccone R., Mina E.D., Bonaglia M.C., Borgatti R., Schaaf C.P., Sutton V.R., Xia Z., Jelluma N., et al. Duplications of FOXG1 in 14q12 are associated with developmental epilepsy, mental retardation, and severe speech impairment. Eur. J. Hum. Genet. 2011, 19:102-107.
13. Bystron I., Blakemore C., Rakic P. Development of the human cerebral cortex: Boulder Committee revisited. Nat. Rev. Neurosci. 2008, 9:110-122.
14. Causeret F., Hidalgo-Sanchez M., Fort P., Backer S., Popoff M.R., Gauthier-Rouvière C., Bloch-Gallego E. Distinct roles of Rac1/Cdc42 and Rho/Rock for axon outgrowth and nucleokinesis of precerebellar neurons toward netrin 1. Development 2004, 131:2841-2852.
15. Chae T., Kwon Y.T., Bronson R., Dikkes P., Li E., Tsai L.H. Mice lacking p35, a neuronal specific activator of Cdk5, display cortical lamination defects, seizures, and adult lethality. Neuron 1997, 18:29-42.
16. Costa M.R., Hedin-Pereira C. Does cell lineage in the developing cerebral cortex contribute to its columnar organization?. Front Neuroanat. 2010, 4:26.
17. Danesin C., Peres J.N., Johansson M., Snowden V., Cording A., Papalopulu N., Houart C. Integration of telencephalic Wnt and hedgehog signaling center activities by Foxg1. Dev. Cell 2009, 16:576-587.
18. Deuel T.A., Liu J.S., Corbo J.C., Yoo S.Y., Rorke-Adams L.B., Walsh C.A. Genetic interactions between doublecortin and doublecortin-like kinase in neuronal migration and axon outgrowth. Neuron 2006, 49:41-53.
19. Dymecki S.M., Kim J.C. Molecular neuroanatomy's " Three Gs" : a primer. Neuron 2007, 54:17-34.
20. Eagleson K.L., Schlueter McFadyen-Ketchum L.J., Ahrens E.T., Mills P.H., Does M.D., Nickols J., Levitt P. Disruption of Foxg1 expression by knock-in of cre recombinase: effects on the development of the mouse telencephalon. Neuroscience 2007, 148:385-399.
21. Franco S.J., Martinez-Garay I., Gil-Sanz C., Harkins-Perry S.R., Müller U. Reelin regulates cadherin function via Dab1/Rap1 to control neuronal migration and lamination in the neocortex. Neuron 2011, 69:482-497.
22. Gleeson J.G., Lin P.T., Flanagan L.A., Walsh C.A. Doublecortin is a microtubule-associated protein and is expressed widely by migrating neurons. Neuron 1999, 23:257-271.
23. Götz M., Huttner W.B. The cell biology of neurogenesis. Nat. Rev. Mol. Cell Biol. 2005, 6:777-788.
24. Govek E.E., Hatten M.E., Van Aelst L. The role of Rho GTPase proteins in CNS neuronal migration. Dev. Neurobiol. 2011, 71:528-553.
25. Hanashima C., Shen L., Li S.C., Lai E. Brain factor-1 controls the proliferation and differentiation of neocortical progenitor cells through independent mechanisms. J. Neurosci. 2002, 22:6526-6536.
26. Hanashima C., Li S.C., Shen L., Lai E., Fishell G. Foxg1 suppresses early cortical cell fate. Science 2004, 303:56-59.
27. Hanashima C., Fernandes M., Hebert J.M., Fishell G. The role of Foxg1 and dorsal midline signaling in the generation of Cajal-Retzius subtypes. J. Neurosci. 2007, 27:11103-11111.
28. Hand R., Bortone D., Mattar P., Nguyen L., Heng J.I., Guerrier S., Boutt E., Peters E., Barnes A.P., Parras C., et al. Phosphorylation of Neurogenin2 specifies the migration properties and the dendritic morphology of pyramidal neurons in the neocortex. Neuron 2005, 48:45-62.
29. Heng J.I., Nguyen L., Castro D.S., Zimmer C., Wildner H., Armant O., Skowronska-Krawczyk D., Bedogni F., Matter J.M., Hevner R., Guillemot F. Neurogenin 2 controls cortical neuron migration through regulation of Rnd2. Nature 2008, 455:114-118.
30. Hevner R.F., Hodge R.D., Daza R.A., Englund C. Transcription factors in glutamatergic neurogenesis: conserved programs in neocortex, cerebellum, and adult hippocampus. Neurosci. Res. 2006, 55:223-233.
31. Hippenmeyer S., Youn Y.H., Moon H.M., Miyamichi K., Zong H., Wynshaw-Boris A., Luo L. Genetic mosaic dissection of Lis1 and Ndel1 in neuronal migration. Neuron 2010, 68:695-709.
32. Hirotsune S., Fleck M.W., Gambello M.J., Bix G.J., Chen A., Clark G.D., Ledbetter D.H., McBain C.J., Wynshaw-Boris A. Graded reduction of Pafah1b1 (Lis1) activity results in neuronal migration defects and early embryonic lethality. Nat. Genet. 1998, 19:333-339.
33. Hong K., Hinck L., Nishiyama M., Poo M.M., Tessier-Lavigne M., Stein E. A ligand-gated association between cytoplasmic domains of UNC5 and DCC family receptors converts netrin-induced growth cone attraction to repulsion. Cell 1999, 97:927-941.
34. Howell B.W., Gertler F.B., Cooper J.A. Mouse disabled (mDab1): a Src binding protein implicated in neuronal development. EMBO J. 1997, 16:121-132.
35. Hu H., Rutishauser U. A septum-derived chemorepulsive factor for migrating olfactory interneuron precursors. Neuron 1996, 16:933-940.
36. Jaglin X.H., Poirier K., Saillour Y., Buhler E., Tian G., Bahi-Buisson N., Fallet-Bianco C., Phan-Dinh-Tuy F., Kong X.P., Bomont P., et al. Mutations in the beta-tubulin gene TUBB2B result in asymmetrical polymicrogyria. Nat. Genet. 2009, 41:746-752.
37. Joshi P.S., Molyneaux B.J., Feng L., Xie X., Macklis J.D., Gan L. Bhlhb5 regulates the postmitotic acquisition of area identities in layers II-V of the developing neocortex. Neuron 2008, 60:258-272.
38. Joyner A.L., Zervas M. Genetic inducible fate mapping in mouse: establishing genetic lineages and defining genetic neuroanatomy in the nervous system. Dev. Dyn. 2006, 235:2376-2385.
39. Karaulanov E., Böttcher R.T., Stannek P., Wu W., Rau M., Ogata S., Cho K.W., Niehrs C. Unc5B interacts with FLRT3 and Rnd1 to modulate cell adhesion in Xenopus embryos. PLoS ONE 2009, 4:e5742.
40. Kawauchi T., Chihama K., Nabeshima Y., Hoshino M. The in vivo roles of STEF/Tiam1, Rac1 and JNK in cortical neuronal migration. EMBO J. 2003, 22:4190-4201.
41. Koizumi H., Tanaka T., Gleeson J.G. Doublecortin-like kinase functions with doublecortin to mediate fiber tract decussation and neuronal migration. Neuron 2006, 49:55-66.
42. Kriegstein A.R., Noctor S.C. Patterns of neuronal migration in the embryonic cortex. Trends Neurosci. 2004, 27:392-399.
43. Kubo K., Honda T., Tomita K., Sekine K., Ishii K., Uto A., Kobayashi K., Tabata H., Nakajima K. Ectopic Reelin induces neuronal aggregation with a normal birthdate-dependent " inside-out" alignment in the developing neocortex. J. Neurosci. 2010, 30:10953-10966.
44. Kwan K.Y., Lam M.M., Krsnik Z., Kawasawa Y.I., Lefebvre V., Sestan N. SOX5 postmitotically regulates migration, postmigratory differentiation, and projections of subplate and deep-layer neocortical neurons. Proc. Natl. Acad. Sci. USA 2008, 105:16021-16026.
45. Labrador J.P., O'keefe D., Yoshikawa S., McKinnon R.D., Thomas J.B., Bashaw G.J. The homeobox transcription factor even-skipped regulates netrin-receptor expression to control dorsal motor-axon projections in Drosophila. Curr. Biol. 2005, 15:1413-1419.
46. Lai T., Jabaudon D., Molyneaux B.J., Azim E., Arlotta P., Menezes J.R., Macklis J.D. SOX5 controls the sequential generation of distinct corticofugal neuron subtypes. Neuron 2008, 57:232-247.
47. Le Guen T., Bahi-Buisson N., Nectoux J., Boddaert N., Fichou Y., Diebold B., Desguerre I., Raqbi F., Daire V.C., Chelly J., Bienvenu T. A FOXG1 mutation in a boy with congenital variant of Rett syndrome. Neurogenetics 2011, 12:1-8.
48. Lodato S., Rouaux C., Quast K.B., Jantrachotechatchawan C., Studer M., Hensch T.K., Arlotta P. Excitatory projection neuron subtypes control the distribution of local inhibitory interneurons in the cerebral cortex. Neuron 2011, 69:763-779.
49. LoTurco J.J., Bai J. The multipolar stage and disruptions in neuronal migration. Trends Neurosci. 2006, 29:407-413.
50. Luo L., Callaway E.M., Svoboda K. Genetic dissection of neural circuits. Neuron 2008, 57:634-660.
51. Manuel M., Martynoga B., Yu T., West J.D., Mason J.O., Price D.J. The transcription factor Foxg1 regulates the competence of telencephalic cells to adopt subpallial fates in mice. Development 2010, 137:487-497.
52. Marín O., Rubenstein J.L. Cell migration in the forebrain. Annu. Rev. Neurosci. 2003, 26:441-483.
53. Martynoga B., Morrison H., Price D.J., Mason J.O. Foxg1 is required for specification of ventral telencephalon and region-specific regulation of dorsal telencephalic precursor proliferation and apoptosis. Dev. Biol. 2005, 283:113-127.
54. Mattar P., Langevin L.M., Markham K., Klenin N., Shivji S., Zinyk D., Schuurmans C. Basic helix-loop-helix transcription factors cooperate to specify a cortical projection neuron identity. Mol. Cell. Biol. 2008, 28:1456-1469.
55. McConnell S.K., Kaznowski C.E. Cell cycle dependence of laminar determination in developing neocortex. Science 1991, 254:282-285.
56. Miyata T., Kawaguchi A., Saito K., Kawano M., Muto T., Ogawa M. Asymmetric production of surface-dividing and non-surface-dividing cortical progenitor cells. Development 2004, 131:3133-3145.
57. Miyoshi G., Fishell G. Directing neuron-specific transgene expression in the mouse CNS. Curr. Opin. Neurobiol. 2006, 16:577-584.
58. Miyoshi G., Fishell G. GABAergic interneuron lineages selectively sort into specific cortical layers during early postnatal development. Cereb. Cortex 2011, 21:845-852.
59. Miyoshi G., Hjerling-Leffler J., Karayannis T., Sousa V.H., Butt S.J., Battiste J., Johnson J.E., Machold R.P., Fishell G. Genetic fate mapping reveals that the caudal ganglionic eminence produces a large and diverse population of superficial cortical interneurons. J. Neurosci. 2010, 30:1582-1594.
60. Molyneaux B.J., Arlotta P., Menezes J.R., Macklis J.D. Neuronal subtype specification in the cerebral cortex. Nat. Rev. Neurosci. 2007, 8:427-437.
61. Morimura T., Ogawa M. Relative importance of the tyrosine phosphorylation sites of Disabled-1 to the transmission of Reelin signaling. Brain Res. 2009, 1304:26-37.
62. Muzio L., Mallamaci A. Foxg1 confines Cajal-Retzius neuronogenesis and hippocampal morphogenesis to the dorsomedial pallium. J. Neurosci. 2005, 25:4435-4441.
63. Nagano T., Morikubo S., Sato M. Filamin A and FILIP (Filamin A-Interacting Protein) regulate cell polarity and motility in neocortical subventricular and intermediate zones during radial migration. J. Neurosci. 2004, 24:9648-9657.
64. Nakamura K., Yamashita Y., Tamamaki N., Katoh H., Kaneko T., Negishi M. In vivo function of Rnd2 in the development of neocortical pyramidal neurons. Neurosci. Res. 2006, 54:149-153.
65. Nguyen L., Besson A., Roberts J.M., Guillemot F. Coupling cell cycle exit, neuronal differentiation and migration in cortical neurogenesis. Cell Cycle 2006, 5:2314-2318.
66. Niwa H., Yamamura K., Miyazaki J. Efficient selection for high-expression transfectants with a novel eukaryotic vector. Gene 1991, 108:193-199.
67. Noctor S.C., Martínez-Cerdeño V., Ivic L., Kriegstein A.R. Cortical neurons arise in symmetric and asymmetric division zones and migrate through specific phases. Nat. Neurosci. 2004, 7:136-144.
68. O'Rourke N.A., Dailey M.E., Smith S.J., McConnell S.K. Diverse migratory pathways in the developing cerebral cortex. Science 1992, 258:299-302.
69. Olson E.C., Walsh C.A. Reelin/Dab1 signaling in the developing cerebral cortex. Reelin Glycoprotein Structure, Biology and Roles in Health and Disease 2008, 89-105. Springer, Berlin, Germany. S.H. Fatemi (Ed.).
70. Pacary E., Heng J., Azzarelli R., Riou P., Castro D., Lebel-Potter M., Parras C., Bell D.M., Ridley A.J., Parsons M., Guillemot F. Proneural transcription factors regulate different steps of cortical neuron migration through Rnd-mediated inhibition of RhoA signaling. Neuron 2011, 69:1069-1084.
71. Rakic P. Neurons in rhesus monkey visual cortex: systematic relation between time of origin and eventual disposition. Science 1974, 183:425-427.
72. Rakic P. Evolution of the neocortex: a perspective from developmental biology. Nat. Rev. Neurosci. 2009, 10:724-735.
73. Ramos R.L., Bai J., LoTurco J.J. Heterotopia formation in rat but not mouse neocortex after RNA interference knockdown of DCX. Cereb. Cortex 2006, 16:1323-1331.
74. Roth M., Bonev B., Lindsay J., Lea R., Panagiotaki N., Houart C., Papalopulu N. FoxG1 and TLE2 act cooperatively to regulate ventral telencephalon formation. Development 2010, 137:1553-1562.
75. Sanada K., Gupta A., Tsai L.H. Disabled-1-regulated adhesion of migrating neurons to radial glial fiber contributes to neuronal positioning during early corticogenesis. Neuron 2004, 42:197-211.
76. Sasaki S., Tabata H., Tachikawa K., Nakajima K. The cortical subventricular zone-specific molecule Svet1 is part of the nuclear RNA coded by the putative netrin receptor gene Unc5d and is expressed in multipolar migrating cells. Mol. Cell. Neurosci. 2008, 38:474-483.
77. Serafini T., Kennedy T.E., Galko M.J., Mirzayan C., Jessell T.M., Tessier-Lavigne M. The netrins define a family of axon outgrowth-promoting proteins homologous to C. elegans UNC-6. Cell 1994, 78:409-424.
78. Sessa A., Mao C.A., Hadjantonakis A.K., Klein W.H., Broccoli V. Tbr2 directs conversion of radial glia into basal precursors and guides neuronal amplification by indirect neurogenesis in the developing neocortex. Neuron 2008, 60:56-69.
79. Shen L., Nam H.S., Song P., Moore H., Anderson S.A. FoxG1 haploinsufficiency results in impaired neurogenesis in the postnatal hippocampus and contextual memory deficits. Hippocampus 2006, 16:875-890.
80. Shen Q., Wang Y., Dimos J.T., Fasano C.A., Phoenix T.N., Lemischka I.R., Ivanova N.B., Stifani S., Morrisey E.E., Temple S. The timing of cortical neurogenesis is encoded within lineages of individual progenitor cells. Nat. Neurosci. 2006, 9:743-751.
81. Shu T., Ayala R., Nguyen M.D., Xie Z., Gleeson J.G., Tsai L.H. Ndel1 operates in a common pathway with LIS1 and cytoplasmic dynein to regulate cortical neuronal positioning. Neuron 2004, 44:263-277.
82. Siegenthaler J.A., Tremper-Wells B.A., Miller M.W. Foxg1 haploinsufficiency reduces the population of cortical intermediate progenitor cells: effect of increased p21 expression. Cereb. Cortex 2008, 18:1865-1875.
83. Sousa V.H., Miyoshi G., Hjerling-Leffler J., Karayannis T., Fishell G. Characterization of Nkx6-2-derived neocortical interneuron lineages. Cereb. Cortex 2009, 19(Suppl 1):i1-i10.
84. Stanco A., Szekeres C., Patel N., Rao S., Campbell K., Kreidberg J.A., Polleux F., Anton E.S. Netrin-1-alpha3beta1 integrin interactions regulate the migration of interneurons through the cortical marginal zone. Proc. Natl. Acad. Sci. USA 2009, 106:7595-7600.
85. Tabata H., Nakajima K. Multipolar migration: the third mode of radial neuronal migration in the developing cerebral cortex. J. Neurosci. 2003, 23:9996-10001.
86. Takemoto M., Hattori Y., Zhao H., Sato H., Tamada A., Sasaki S., Nakajima K., Yamamoto N. Laminar and areal expression of unc5d and its role in cortical cell survival. Cereb. Cortex 2011, 21:1925-1934.
87. Tan S.S., Breen S. Radial mosaicism and tangential cell dispersion both contribute to mouse neocortical development. Nature 1993, 362:638-640.
88. Tarabykin V., Stoykova A., Usman N., Gruss P. Cortical upper layer neurons derive from the subventricular zone as indicated by Svet1 gene expression. Development 2001, 128:1983-1993.
89. Torii M., Hashimoto-Torii K., Levitt P., Rakic P. Integration of neuronal clones in the radial cortical columns by EphA and ephrin-A signalling. Nature 2009, 461:524-528.
90. Trommsdorff M., Gotthardt M., Hiesberger T., Shelton J., Stockinger W., Nimpf J., Hammer R.E., Richardson J.A., Herz J. Reeler/Disabled-like disruption of neuronal migration in knockout mice lacking the VLDL receptor and ApoE receptor 2. Cell 1999, 97:689-701.
91. Tsai J.W., Bremner K.H., Vallee R.B. Dual subcellular roles for LIS1 and dynein in radial neuronal migration in live brain tissue. Nat. Neurosci. 2007, 10:970-979.
92. Uchida T., Baba A., Pérez-Martínez F.J., Hibi T., Miyata T., Luque J.M., Nakajima K., Hattori M. Downregulation of functional Reelin receptors in projection neurons implies that primary Reelin action occurs at early/premigratory stages. J. Neurosci. 2009, 29:10653-10662.
93. Westerlund N., Zdrojewska J., Padzik A., Komulainen E., Björkblom B., Rannikko E., Tararuk T., Garcia-Frigola C., Sandholm J., Nguyen L., et al. Phosphorylation of SCG10/stathmin-2 determines multipolar stage exit and neuronal migration rate. Nat. Neurosci. 2011, 14:305-313.
94. Xu B., Goldman J.S., Rymar V.V., Forget C., Lo P.S., Bull S.J., Vereker E., Barker P.A., Trudeau L.E., Sadikot A.F., Kennedy T.E. Critical roles for the netrin receptor deleted in colorectal cancer in dopaminergic neuronal precursor migration, axon guidance, and axon arborization. Neuroscience 2010, 169:932-949.
95. Xuan S., Baptista C.A., Balas G., Tao W., Soares V.C., Lai E. Winged helix transcription factor BF-1 is essential for the development of the cerebral hemispheres. Neuron 1995, 14:1141-1152.
96. Yamagishi S., Hampel F., Hata K., Del Toro D., Schwark M., Kvachnina E., Bastmeyer M., Yamashita T., Tarabykin V., Klein R., Egea J. FLRT2 and FLRT3 act as repulsive guidance cues for Unc5-positive neurons. EMBO J. 2011, 30:2920-2933.
97. Yao J., Lai E., Stifani S. The winged-helix protein brain factor 1 interacts with groucho and hes proteins to repress transcription. Mol. Cell. Biol. 2001, 21:1962-1972.
98. Yoshida M., Assimacopoulos S., Jones K.R., Grove E.A. Massive loss of Cajal-Retzius cells does not disrupt neocortical layer order. Development 2006, 133:537-545.
99. Yu Y.C., Bultje R.S., Wang X., Shi S.H. Specific synapses develop preferentially among sister excitatory neurons in the neocortex. Nature 2009, 458:501-504.
100. Zirlinger M., Lo L., McMahon J., McMahon A.P., Anderson D.J. Transient expression of the bHLH factor neurogenin-2 marks a subpopulation of neural crest cells biased for a sensory but not a neuronal fate. Proc. Natl. Acad. Sci. USA 2002, 99:8084-8089.