Mudanças entre as edições de "Genes controlling pattern formation in Drosophila embryogenesis"

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| ''Trunk'' (trk) || Maternal mRNA translated in early embryo, protein released into preivitelline space || Similar to ''tor'' || Secreted protein || Probably ligand of ''tor'', after processing by ''tsl''
 
| ''Trunk'' (trk) || Maternal mRNA translated in early embryo, protein released into preivitelline space || Similar to ''tor'' || Secreted protein || Probably ligand of ''tor'', after processing by ''tsl''
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{| border="1"
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|+ '''Zygotic Anteroposterior Gap Class'''
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! Gene !! Expression Pattern !! Mutant Phenotype !! Molecular Nature !! Developmental Function
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| ''empty spiracles'' || Transcription during blastoderm 78-67% EL; later, in cells forming tracheal pits and spiracles || Defects in antennal segment, tracheal system || Transcriptional regulator (homeodomain) || Specifies procephalic segments
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| ''giant'' (gt) || Initial transcription at preblastoderm stage 82-60% and 33-0% EL; changes later || Defects in or absence of labrum, labium, and abdominal segments || Transcriptional regulator (Leucine zipper) || Activates ''Scr''; represses ''Kr''
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| ''huckebein'' (hkb) || Anterior and posterior ends of blastoderm || Defects in terminal body structures and gut || Transcriptional regulator (zinc finger domain) || Specifies terminal structures in concert with ''tll''
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| ''hunchback'' (hb) || Maternal mRNA initially uniform; protein forms anteroposterior gradient. Embryonic transcription 100-50% EL and 20-10% EL. Posterior domain long-lasting. || Embryonic: deletion of labium, thorax, aA7/pA8 (PS 13). No pure maternal effect, but if mother and sperm are ''hb''-, then deletion of all mouthparts and thoracic segments and A1-A3, with mirror duplication of abdomen. || Transcriptional regulator (zinc finger domain) || Represses ''kni''; represses ''Kr'' at high level and activates at low level; regulates ''eve''; regulates ''h'', ''run'', ''ftz''; activates ''Antp'' (with ''ftz''); represses ''Ubx''
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| ''knirps'' (kni) || Transcription starts at preblastoderm stage forming zone 45-30% EL. Ventral patch and narrow ring form in atnerior by cellular blastoderm stage. || Replacement of A1-A7 by single A-type segment || Transcriptional regulator (zinc finguer) || Represses ''Kr''; regulates ''h'', ''run'', ''eve'', ''ftz''; represses ''Abd-B'' and ''Antp''
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| ''Krüppel'' (Kr) || Transcription starts at preblastoderm stage in central zone, eventually expanding to 60-30% EL. Later also posterior patch and patch in head. || Purely embryonic. Head normal, deletion of thorax and A1-A5. Duplicated inverted A6. || Trancriptional regulator (zinc finguer) || Activates ''kni''; represses ''gt''; regulates ''eve''; regulates ''h'', ''run'', ''ftz''; represses ''Scr''; activates ''Antp''; represses ''Abd-B''
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| ''orthodenticle'' (otd) || Narrow band (75-92% EL) in anterior blastoderm || Defects in eyes and anterior head parts || Transcriptional regulator (homeodomain, paired domain) || Activated by ''bcd'' and ''tor'', ''otd'' - along with ''ems'' - specifies procephalic segments
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| ''tailless'' (tll) || Transcription in termini of preblastoderm embryo || Head skeleton reduced but labrum present. Hindgut, Malpighian tubules absent. || Transcriptional regulator (steroid receptor family) || Activates ''hb''; represses ''Kr''; represses ''kni''; activates ''h''
 
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Edição das 17h24min de 24 de novembro de 2006

Maternal Anteroposterior Axis
Gene Expression Pattern Mutant Phenotype Molecular Nature Developmental Function
dicephalic (dic) Maternal Abnormal position of nurse cells relative to oocyte Contributes to anteroposterior polarity of nurse cell oocyte complex
gurken (grk) Oocyte Eggs ventralized with dorsal appendages reduced or missing Similar to vertebrate transforming growth factor alpha (TGF-α), ligand for torpedo Establishes first posterior and then dorsal identity of ovarian follicle cells
spindle (spn) (several loci) Maternal germ line Disturbed anteroposterior polarity of oocyte Determination of prospective oocyte among cystocytes
torpedo (trp) Ovarian follicle cells Similar to grk Receptor tyrosine kinase, receptor for grk Same as grk
Maternal Anterior Class
Gene Expression Pattern Mutant Phenotype Molecular Nature Developmental Function
bicoid (bcd) mRNA transcribed in nurse cells and transported to anterior of oocyte. Translated during cleavage. Protein forms anteroposterior gradient. Head and thorax replaced with mirror image of telson Transcriptional regulator (homeodomain and paired repeat) Activates hb transcription; acts as a morphogen on embryonic genes; expressed anteriorly
exuperantia (exu) Testis and ovary Reducion of head; defective gastrulation RNA-binding protein Needed to transport bcd mRNA from nurse cells to oocyte
hunchback (hb) See Zygotic anteroposterior gap class
staufen (stau) Maternal germ line, emryonic central nervous system Most abdominal segments missing, no pole cells, also head defects Double-stranded RNA-binding protein Required for bicoid mRNA localization and polar granule assembly
swallow (swa) Maternal germ line Reduction of head; cellularization defects Rna-binding protein Required for localization of bcd mRNA
Maternal Posterior Class
Gene Expression Pattern Mutant Phenotype Molecular Nature Developmental Function
cappuccino (capu) Maternal Abdominal segments A2-A7 missing; no pole cells Putative transmembrane receptor Required for polar granule assembly
nanos Transcription in oocyte and nurse cells. Partial localization to polar granules. Only this localized mRNA is translated. Absence of abdomen; pole cells normal RNA-binding protein, translational repressor Inhibits translation of maternal hb mRNA and hastens its destruction, hence allows activation of kni in posterior.
oskar (osk) Maternal germ line Similar to capu Required for polar granule assembly, localizes nos mRNA
pumilio (pum) Transcription maternal. Protein probably localized to posterior Most of abdomen missing; pole cells normal RNA-binding protein Recruits nos protein to hb mRNA
spire (spir) Maternal Similar to capu Actin-binding protein Required for polar granule assembly
staufen (stau) See maternal anterior system
tudor (tud) Male and female germ line Similar to capu Required for pole cell formation
vasa (vas) Transcription in nurse cells and oocyte; mRNA uniform in early embryo. Protein localized in posterior of oocyte, egg, and in pole cells. Similar to capu RNA helicase Required for pole cell formation
Maternal Terminal Class
Gene Expression Pattern Mutant Phenotype Molecular Nature Developmental Function
NTF-1 Transcriptional inhibitor Inhibits transcription of hkb and tll
torso (tor) Transcription in nurse cells. Transport to oocyte, where protein distributed uniformly in plasma membrane. Absence of labrum, reduction of head skeleton, absence of A8 and telson; gain of function; suppression of segmentation in thorax and abdomen Tyrosine kinase receptor, likely receptor for active trunk protein Activates tll hkb by inhibiting NTF-1
torsolike (tsl) Protein secreted by anterior and posterior ovarian follicle cells probably associates with vitelline envelope near egg poles Similar to tolr (loss of function only) Modifying protein Generates active form of trunk near egg poles
Trunk (trk) Maternal mRNA translated in early embryo, protein released into preivitelline space Similar to tor Secreted protein Probably ligand of tor, after processing by tsl
Zygotic Anteroposterior Gap Class
Gene Expression Pattern Mutant Phenotype Molecular Nature Developmental Function
empty spiracles Transcription during blastoderm 78-67% EL; later, in cells forming tracheal pits and spiracles Defects in antennal segment, tracheal system Transcriptional regulator (homeodomain) Specifies procephalic segments
giant (gt) Initial transcription at preblastoderm stage 82-60% and 33-0% EL; changes later Defects in or absence of labrum, labium, and abdominal segments Transcriptional regulator (Leucine zipper) Activates Scr; represses Kr
huckebein (hkb) Anterior and posterior ends of blastoderm Defects in terminal body structures and gut Transcriptional regulator (zinc finger domain) Specifies terminal structures in concert with tll
hunchback (hb) Maternal mRNA initially uniform; protein forms anteroposterior gradient. Embryonic transcription 100-50% EL and 20-10% EL. Posterior domain long-lasting. Embryonic: deletion of labium, thorax, aA7/pA8 (PS 13). No pure maternal effect, but if mother and sperm are hb-, then deletion of all mouthparts and thoracic segments and A1-A3, with mirror duplication of abdomen. Transcriptional regulator (zinc finger domain) Represses kni; represses Kr at high level and activates at low level; regulates eve; regulates h, run, ftz; activates Antp (with ftz); represses Ubx
knirps (kni) Transcription starts at preblastoderm stage forming zone 45-30% EL. Ventral patch and narrow ring form in atnerior by cellular blastoderm stage. Replacement of A1-A7 by single A-type segment Transcriptional regulator (zinc finguer) Represses Kr; regulates h, run, eve, ftz; represses Abd-B and Antp
Krüppel (Kr) Transcription starts at preblastoderm stage in central zone, eventually expanding to 60-30% EL. Later also posterior patch and patch in head. Purely embryonic. Head normal, deletion of thorax and A1-A5. Duplicated inverted A6. Trancriptional regulator (zinc finguer) Activates kni; represses gt; regulates eve; regulates h, run, ftz; represses Scr; activates Antp; represses Abd-B
orthodenticle (otd) Narrow band (75-92% EL) in anterior blastoderm Defects in eyes and anterior head parts Transcriptional regulator (homeodomain, paired domain) Activated by bcd and tor, otd - along with ems - specifies procephalic segments
tailless (tll) Transcription in termini of preblastoderm embryo Head skeleton reduced but labrum present. Hindgut, Malpighian tubules absent. Transcriptional regulator (steroid receptor family) Activates hb; represses Kr; represses kni; activates h