title: Regional and segmental differences in the embryonic expression of a putative leech Hox gene, Lox2, by central neurons immunoreactive to FMRFamide-like neuropeptides.
abstract: We performed immunofluorescence experiments using a rat polyclonal antibody on formaldehyde-fixed whole-mount embryos to characterize the expression of a putative leech Hox gene, Lox2, during embryonic development. The main goal was to determine whether the differentiation of subsets of FMRFamide-like immunoreactive (FLI) neurons coincide with the expression domain of Lox2. The earliest expression of Lox2 was detected in relatively large, prominent nuclei in the posterior region at embryonic day 4, a very early stage. Lox2 expression was also detected in subsets of central neurons (neurons located in the CNS) located in midbody ganglia 6 (M6)-M21. In addition, Lox2 was expressed by a number of segment-specific and segmentally repeated central FLI neurons. Lox2-positive FLI neurons of interest included some of those previously identified: the rostral most ventral (RMV) neurons, the circular ventral (CV) neurons, and cell 261. The paired RMVs, which are located in all midbody ganglia, expressed Lox2 only in M7-M19. The CV neurons, specialized motor neurons that innervate the circular ventral muscles of the body wall, expressed Lox2 in M7-M19. The putative cell 261 expressed Lox2 in M7-M12, where Lox1 is also expressed. FMRFamide staining in putative segmental homologs of cell 261 was not detected in other segmental ganglia. Our results suggest a role for Lox2 in very early embryonic development (before the formation of the CNS), and in the differentiation of segmentally repeated and region-specific FLI neurons.
authors: Department of Biological Sciences, Lehman College, The City University of New York, Bronx, NY, 10468, USA, rajeng2@yahoo.com.
authors: Rajendra
authors: R
authors: Gharbaran
authors: Susana
authors: S
authors: Alvarado
authors: Gabriel O
authors: GO
authors: Aisemberg
mesh_terms: D000818:Animals; D002490:Central Nervous System / Q000196:embryology* / Q000378:metabolism; D004625:Embryo, Nonmammalian; D047108:Embryonic Development; D019835:FMRFamide / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D018398:Homeodomain Proteins / Q000096:biosynthesis*; D007150:Immunohistochemistry; D007865:Leeches / Q000196:embryology* / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism
chemical_list: D018398:Homeodomain Proteins; C583399:Lox2 protein, Hirudo medicinalis; D009479:Neuropeptides; D019835:FMRFamide
references: Bioessays. 1992 Apr;14(4):245-52
references: 1350721
references: Dev Dyn. 2009 Mar;238(3):755-65
references: 19235717
references: Proc Biol Sci. 2007 Jun 22;274(1617):1481-7
references: 17426015
references: Development. 2005 Jun;132(12):2861-71
references: 15930115
references: J Neurosci. 1995 Aug;15(8):5551-9
references: 7643200
references: J Neurosci. 2006 Oct 18;26(42):10925-33
references: 17050731
references: Cell. 1993 Dec 31;75(7):1333-49
references: 7903601
references: Annu Rev Genet. 1996;30:529-56
references: 8982464
references: J Comp Neurol. 1980 Mar 15;190(2):283-302
references: 7381060
references: Curr Genomics. 2012 Jun;13(4):278-88
references: 23204917
references: Dev Suppl. 1994;:61-77
references: 7579525
references: J Neurosci. 1985 Sep;5(9):2310-7
references: 4031997
references: J Neurophysiol. 2007 Feb;97(2):1405-12
references: 17167060
references: Development. 1992 Nov;116(3):697-710
references: 1363227
references: Mech Dev. 2006 Apr;123(4):321-33
references: 16644189
references: PLoS One. 2008;3(12):e4004
references: 19104667
references: Int Rev Neurobiol. 1992;33:109-93
references: 1592567
references: Cell Mol Neurobiol. 2012 Nov;32(8):1243-53
references: 22569741
references: Development. 2008 Jan;135(1):171-82
references: 18065432
references: Development. 1993 Aug;118(4):1063-75
references: 7903632
references: Nature. 1996 Dec 19-26;384(6610):630-4
references: 8967950
references: J Neurosci. 1987 Sep;7(9):2618-29
references: 3625266
references: Development. 1993 Oct;119(2):319-38
references: 8287791
references: Nature. 1995 May 4;375(6526):58-61
references: 7723843
references: Parasitol Res. 2004 Sep;94(2):118-24
references: 15322921
references: Dev Biol. 1997 Oct 15;190(2):284-300
references: 9344545
references: Annu Rev Cell Dev Biol. 2009;25:431-56
references: 19575673
references: Nature. 1989 Oct 26;341(6244):760-3
references: 2571941
references: J Neurobiol. 1994 Jun;25(6):640-51
references: 7915301
references: Theory Biosci. 2006 Mar;124(3-4):371-96
references: 17046366
references: Parasitol Int. 2008 Mar;57(1):8-17
references: 17977060
references: PLoS One. 2012;7(4):e34762
references: 22485187
references: Development. 1998 Jan;125(2):279-91
references: 9486801
references: Genomics. 2010 May;95(5):250-5
references: 19944143
references: Int J Dev Neurosci. 2013 Apr;31(2):105-15
references: 23220224
references: Development. 1997 Nov;124(22):4505-14
references: 9409668
references: Development. 1999 Dec;126(24):5819-31
references: 10572056
references: EXS. 1995;72:77-87
references: 7833622
references: J Neurosci. 2005 Mar 9;25(10):2478-89
references: 15758156
references: J Embryol Exp Morphol. 1982 Dec;72:71-96
references: 7183746
references: J Comp Neurol. 1991 Nov 15;313(3):431-40
references: 1770166
references: Dev Biol. 2004 May 1;269(1):137-51
references: 15081363
references: EMBO J. 1985 Aug;4(8):2035-43
references: 16453630
references: Curr Top Dev Biol. 2009;88:103-37
references: 19651303
references: Nature. 2013 Jan 24;493(7433):526-31
references: 23254933
references: Protein Expr Purif. 2002 Nov;26(2):260-5
references: 12406680
references: Development. 1998 May;125(9):1579-89
references: 9521896
references: Genes Dev. 1990 Sep;4(9):1573-87
references: 1979297
references: Mol Phylogenet Evol. 2005 Mar;34(3):616-24
references: 15683933
references: Brain Res. 1996 Jun 3;723(1-2):115-24
references: 8813388
references: Dev Genes Evol. 1998 Nov;208(9):517-22
references: 9799433
references: Evol Dev. 2001 May-Jun;3(3):145-53
references: 11440249
references: J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2006 Feb;192(2):123-33
references: 16205960
references: J Exp Biol. 1992 Sep;170:71-92
references: 1402613
references: J Neurophysiol. 1979 Mar;42(2):455-64
references: 422973
references: J Physiol. 1970 Aug;209(3):627-46
references: 5499800
references: Dev Genes Evol. 1998 Mar;208(1):51-5
references: 9518525
references: J Neurosci. 1987 Jun;7(6):1911-8
references: 3598654