Fate map of the eye-antennal imaginal disc of the tumorous-head mutant of Drosophila melanogaster

Development ◽  
1987 ◽  
Vol 100 (2) ◽  
pp. 261-269
Author(s):  
D.J. Andrew
Keyword(s):  
Imaginal Disc ◽  
Abdominal Tergite ◽  
External Genitalia ◽  
Wild Type ◽  
Fate Map ◽  
Developmental Potential ◽  
Eye Disc ◽  
Female External Genitalia ◽  
Antennal Disc ◽  
Genital Tissue

In specific genetic backgrounds, a mutation in the tuh-3 gene results in the homeotic transformation of head structures to either leg disc derivatives or structures normally found in the extreme posterior end of wild-type animals. The origins of the homeotic structures were mapped to defined positions in the eye-antennal imaginal disc by transplanting abnormal regions of discs isolated from tuh-3 mutants into host mwh;e4 larvae. These metamorphosed implants were removed and differentiated structures were identified. Of 211 successfully recovered implants, 157 gave rise to homeotic tissue: abdominal tergite, male or female external genitalia and/or leg tissue. Transformations to abdominal tergite occurred primarily in cells taken from the eye region of the compound disc. Male and female genitalia arose most often in implants taken from the antennal portion of the disc, although some tissue taken from the lateral region of the eye disc also gave rise to external genitalia. Leg structures came exclusively from implants from the antennal region of the imaginal disc. These results suggest that cells from within specific regions of the eye-antennal compound disc are constrained in their developmental potential. An obvious constraint observed with this mutation is a dorsal/ventral one: Cells from the eye disc, a dorsal structure, primarily gave rise to other dorsal structures, abdominal tergite tissue. Cells from the antennal disc, a ventrally derived structure, primarily gave rise to other ventral structures including genital tissue and distal leg.

Establishing primordia in the Drosophila eye-antennal imaginal disc: the roles of decapentaplegic, wingless and hedgehog

Development ◽  
1997 ◽  
Vol 124 (23) ◽  
pp. 4793-4800 ◽  
Author(s):  
J. Royet ◽  
R. Finkelstein
Keyword(s):  
Drosophila Melanogaster ◽  
Imaginal Disc ◽  
Compound Eye ◽  
Head Capsule ◽  
Imaginal Discs ◽  
Model System ◽  
Morphogenetic Furrow ◽  
Excellent Model ◽  
Eye Disc ◽  
Antennal Disc

The eye-antennal imaginal discs of Drosophila melanogaster form the head capsule of the adult fly. Unlike the limb primordia, each eye-antennal disc gives rise to morphologically and functionally distinct structures. As a result, these discs provide an excellent model system for determining how the fates of primordia are specified during development. In this study, we investigated how the adjacent primordia of the compound eye and dorsal head vertex are specified. We show that the genes wingless (wg) and orthodenticle (otd) are expressed throughout the entire second instar eye-antennal disc, conferring a default fate of dorsal vertex cuticle. Activation of decapentaplegic (dpp) expression in the posterior eye disc eliminates wg and otd expression, thereby permitting eye differentiation. We also demonstrate that otd is activated by wg in the vertex primordium. Finally, we show that early activation of dpp depends on hedgehog (hh) expression in the eye anlage prior to morphogenetic furrow formation.

The development of the sensory neuron pattern in the antennal disc of wild-type and mutant (lz3, ssa) Drosophila melanogaster

Development ◽  
1991 ◽  
Vol 112 (4) ◽  
pp. 1063-1075
Author(s):  
M.C. Lienhard ◽  
R.F. Stocker
Keyword(s):  
Drosophila Melanogaster ◽  
Sensory Neuron ◽  
Antennal Segment ◽  
Wild Type ◽  
Homeotic Mutant ◽  
In The Wild ◽  
The Brain ◽  
Antennal Disc ◽  
Antennal Nerve

The development of the sensory neuron pattern in the antennal disc of Drosophila melanogaster was studied with a neuron-specific monoclonal antibody (22C10). In the wild type, the earliest neurons become visible 3 h after pupariation, much later than in other imaginal discs. They lie in the center of the disc and correspond to the neurons of the adult aristal sensillum. Their axons join the larval antennal nerve and seem to establish the first connection towards the brain. Later on, three clusters of neurons appear in the periphery of the disc. Two of them most likely give rise to the Johnston's organ in the second antennal segment. Neurons of the olfactory third antennal segment are formed only after eversion of the antennal disc (clusters t1-t3). The adult pattern of antennal neurons is established at about 27% of metamorphosis. In the mutant lozenge3 (lz3), which lacks basiconic antennal sensilla, cluster t3 fails to develop. This indicates that, in the wild type, a homogeneous group of basiconic sensilla is formed by cluster t3. The possible role of the lozenge gene in sensillar determination is discussed. The homeotic mutant spineless-aristapedia (ssa) transforms the arista into a leg-like tarsus. Unlike leg discs, neurons are missing in the larval antennal disc of ssa. However, the first neurons differentiate earlier than in normal antennal discs. Despite these changes, the pattern of afferents in the ectopic tarsus appears leg specific, whereas in the non-transformed antennal segments a normal antennal pattern is formed. This suggests that neither larval leg neurons nor early aristal neurons are essential for the outgrowth of subsequent afferents.

46, XY Disorder of Sexual Development with Ambiguous Female External Genitalia: A Case Report

2021 ◽  
Vol 10 (1) ◽  
pp. 45-47
Author(s):  
Anil Kumar Sah ◽  
Bipin Maharjan ◽  
Mahesh Bahadur Adhikari ◽  
Suman Baral ◽  
Mimi Giri
Keyword(s):  
Case Report ◽  
Sexual Development ◽  
Dehydrogenase Deficiency ◽  
External Genitalia ◽  
Hydroxysteroid Dehydrogenase ◽  
Androgen Action ◽  
Disorder Of Sexual Development ◽  
Insufficiency Syndrome ◽  
Atypical Development ◽  
Female External Genitalia

Disorder of Sexual Development (DSD) is a group of congenital conditions with atypical development of sex at chromosomal, gonadal or anatomic level. Genetic males with DSD (46 XY DSD) can present with female external genital phenotype, ambiguous, or a micropenis. It is caused by incomplete intrauterine masculinization with or without the presence of Müllerian structures. It results either from decreased synthesis of testosterone or DHT or from impairment of androgen action. Herein, we report a case of a 13-year child raised as female with hoarseness of voice and gradual enlargement of clitoris with hormonal assessment not suggestive of either 5 Alfa Reductase deficiency, Congenital Adrenal Insufficiency Syndrome or 17β-Hydroxysteroid Dehydrogenase deficiency

scholarly journals Sex-Determining Gene(s) on Distal 9p: Clinical and Molecular Studies in Six Cases*

2000 ◽  
Vol 85 (9) ◽  
pp. 3094-3100 ◽  
Author(s):  
Koji Muroya ◽  
Torayuki Okuyama ◽  
Keiji Goishi ◽  
Yoshifumi Ogiso ◽  
Shin Fukuda ◽  
...  
Keyword(s):  
Wide Spectrum ◽  
External Genitalia ◽  
Chromosome 9 ◽  
Severe Malnutrition ◽  
Female Case ◽  
Dm Domain ◽  
Baseline Values ◽  
Male External Genitalia ◽  
Female External Genitalia

Abstract We report on clinical and molecular findings in five karyotypic males (cases 1–5) and one karyotypic female (case 6) with distal 9p monosomy. Cases 1–3 and 6 had female external genitalia, case 4 showed ambiguous external genitalia, and case 5 exhibited male external genitalia with left cryptorchidism and right intrascrotal testis. Gonadal explorations at gonadectomy in cases 3 and 4 revealed that case 3 had left streak gonad and right agonadism, and case 4 had bilateral hypoplastic testes. Endocrine studies in cases 1–4 and 6 showed that cases 1, 3, and 6 had definite primary hypogonadism, with basal FSH levels of 54, 39, and 41 IU/L, respectively, whereas case 2 with severe malnutrition was unremarkable for the baseline values, and case 4 had fairly good testicular function. Fluorescence in situ hybridization and microsatellite analyses demonstrated that all cases had hemizygosity of the 9p sex-determining region distal to D9S1779, with loss of the candidate sex-determining genes DMRT1 and DMRT2 from the abnormal chromosome 9. Sequence analysis in cases 1–4 and 6 showed that they had normal sequences of each exon of DMRT1 and the DM domain of DMRT2 on the normal chromosome 9, and that cases 1–4 had normal SRY sequence. The results provide further support for the presence of a sex-determining gene(s) on distal 9p and favor the possibility of DMRT1 and/or DMRT2 being the sex-determining gene(s). Furthermore, as hemizygosity of the 9p sex-determining region was associated with a wide spectrum of gonadogenesis from agonadism to testis formation in karyotypic males and with primary hypogonadism regardless of karyotypic sex, it is inferred that haploinsufficiency of the 9p sex-determining gene(s) primarily hinders the formation of indifferent gonad, leading to various degrees of defective testis formation in karyotypic males and impaired ovary formation in karyotypic females.

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