Control of Drosophila adult pattern by extradenticle

S. Gonzalez-Crespo; G. Morata

doi:10.1242/dev.121.7.2117

Control of Drosophila adult pattern by extradenticle

Development ◽

10.1242/dev.121.7.2117 ◽

1995 ◽

Vol 121 (7) ◽

pp. 2117-2125 ◽

Cited By ~ 15

Author(s):

S. Gonzalez-Crespo ◽

G. Morata

Keyword(s):

Homeobox Gene ◽

Homeotic Genes ◽

Body Parts ◽

Developmental Processes ◽

Adult Pattern ◽

Homeotic Mutations ◽

Ectopic Eyes

The homeobox gene extradenticle (exd) acts as a cofactor of the homeotic genes in the specification of larval patterns during embryogenesis. To study its role in adult patterns, we have generated clones of mutant exd- cells and examined their effect on the different body parts. In some regions, exd- clones exhibit homeotic transformations similar to those produced by known homeotic mutations such as Ultrabithorax (Ubx), labial (lab), spineless-aristapedia (ssa) or Antennapedia (Antp). In other regions, the lack of exd causes novel homeotic transformations producing ectopic eyes and legs. Moreover, exd is also required for functions normally not associated with homeosis, such as the maintenance of the dorsoventral pattern, the specification of subpatterns in adult appendages or the arrangement of bristles in the mesonotum and genitalia. Our findings indicate that exd is critically involved in adult morphogenesis, not only in the homeotic function but also in several other developmental processes.

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Hox genes and the evolution of vertebrate axial morphology

Development ◽

10.1242/dev.121.2.333 ◽

1995 ◽

Vol 121 (2) ◽

pp. 333-346 ◽

Cited By ~ 55

Author(s):

A.C. Burke ◽

C.E. Nelson ◽

B.A. Morgan ◽

C. Tabin

Keyword(s):

Hox Genes ◽

Cervical Vertebrae ◽

Homeobox Gene ◽

Paraxial Mesoderm ◽

Thoracic Vertebrae ◽

Homeotic Genes ◽

Evolutionary Variation ◽

Axial Morphology ◽

Anterior Posterior ◽

Anterior Posterior Axis

A common form of evolutionary variation between vertebrate taxa is the different numbers of segments that contribute to various regions of the anterior-posterior axis; cervical vertebrae, thoracic vertebrae, etc. The term ‘transposition’ is used to describe this phenomenon. Genetic experiments with homeotic genes in mice have demonstrated that Hox genes are in part responsible for the specification of segmental identity along the anterior-posterior axis, and it has been proposed that an axial Hox code determines the morphology of individual vertebrae (Kessel, M. and Gruss, P. (1990) Science 249, 347–379). This paper presents a comparative study of the developmental patterns of homeobox gene expression and developmental morphology between animals that have homologous regulatory genes but different morphologies. The axial expression boundaries of 23 Hox genes were examined in the paraxial mesoderm of chick, and 16 in mouse embryos by in situ hybridization and immunolocalization techniques. Hox gene anterior expression boundaries were found to be transposed in concert with morphological boundaries. This data contributes a mechanistic level to the assumed homology of these regions in vertebrates. The recognition of mechanistic homology supports the historical homology of basic patterning mechanisms between all organisms that share these genes.

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Effects of ectopic expression of caudal during Drosophila development

Development ◽

10.1242/dev.109.2.271 ◽

1990 ◽

Vol 109 (2) ◽

pp. 271-277 ◽

Cited By ~ 5

Author(s):

M. Mlodzik ◽

G. Gibson ◽

W.J. Gehring

Keyword(s):

Heat Shock ◽

Imaginal Disc ◽

Ectopic Expression ◽

Homeobox Gene ◽

Homeotic Genes ◽

Posterior Half ◽

Fushi Tarazu ◽

Drosophila Development ◽

Head Development ◽

Cad Protein

The effects of heat-shock-induced ectopic expression of the homeobox gene caudal (cad) at all stages of Drosophila development have been examined. Presence of cad protein (CAD) at the anterior end of cellular blastoderm embryos was found to disrupt head development and segmentation, due to alteration of the expression of segmentation genes such as fushi tarazu and engrailed, as well as repression of head-determining genes such as Deformed. These results support the conclusion that, while CAD is probably required to activate transcription of fushi tarazu in the posterior half of the embryo, it should not be expressed in the anterior half prior to gastrulation, and thus suggest a role for the CAD gradient. Ectopic expression of CAD at later stages of development has no obvious effects on embryogenesis or imaginal disc development, suggesting that the homeotic genes of the Antennapedia and Bithorax Complexes are almost completely epistatic to caudal.

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Lymphoid expression and TATAA binding of a human protein containing an Antennapedia homeodomain

Blood ◽

10.1182/blood.v78.4.1047.bloodjournal7841047 ◽

1991 ◽

Vol 78 (4) ◽

pp. 1047-1055

Author(s):

LJ Baier ◽

MC Hannibal ◽

EW Hanley ◽

GJ Nabel

Keyword(s):

Dna Binding ◽

B Cell ◽

Messenger Rna ◽

Binding Protein ◽

Homeobox Gene ◽

Lymphoid Cells ◽

Regulatory Function ◽

Homeotic Genes ◽

Expression Library ◽

Alternative Function

In an effort to identify human proteins that bind to the TATAA box, a lambda gt-11 expression library was screened with a radiolabeled DNA probe containing 12 copies of the TATAA sequence. A cDNA encoding a specific TATAA binding protein was isolated and found to contain a homeobox domain identical at 59 of 60 residues to the Drosophila Antennapedia (Antp) homeodomain, as well as another conserved motif found in homeotic genes, the homeo-specific pentapeptide. Although this and other Antp-like homeobox proteins have been described previously in neuronal cells and fibroblasts, we report the expression of this gene in lymphoid cells. This cDNA, isolated from a B-cell library, hybridizes to a 1.6-kb messenger RNA in several T- and B-cell lines, and the expected protein was identified in Jurkat T-lymphoid cells by Western blot analysis. The DNA binding specificity of this human Antp clone was analyzed using single-base mutations of the TATAA sequence. The first thymidine, as well as the last three bases (TAA), were important for homeobox binding. Finally, the function of the highly conserved homeospecific pentapeptide protein region was investigated in both the human and Drosophila Antp proteins. The homeospecific pentapeptide region was not required for DNA binding, and Drosophila Antp proteins mutated in the pentapeptide region were able to transactivate the Ubx promoter in Schneider L2 cells, in contrast to a homeodomain mutation, suggesting an alternative function for the homeospecific pentapeptide in homeotic genes. Because the human Antp TATAA binding protein is expressed in both lymphoid and non-lymphoid cells, we suggest that this homeobox gene has evolved a more general transcriptional regulatory function in higher eukaryotic cells.

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The Homeobox Gene cut Interacts Genetically With the Homeotic Genes proboscipedia and Antennapedia

Genetics ◽

10.1093/genetics/149.1.131 ◽

1998 ◽

Vol 149 (1) ◽

pp. 131-142

Author(s):

Laura A Johnston ◽

Bruce D Ostrow ◽

Christine Jasoni ◽

Karen Blochlinger

Keyword(s):

Expression Patterns ◽

Significant Proportion ◽

Ectopic Expression ◽

Homeobox Gene ◽

Homeodomain Protein ◽

Homeotic Genes ◽

Loss Of Function ◽

Regulation Of Expression ◽

Segmental Identity

Abstract The cut locus (ct) codes for a homeodomain protein (Cut) and controls the identity of a subset of cells in the peripheral nervous system in Drosophila. During a screen to identify ct-interacting genes, we observed that flies containing a hypomorphic ct mutation and a heterozygous deletion of the Antennapedia complex exhibit a transformation of mouthparts into leg and antennal structures similar to that seen in homozygous proboscipedia (pb) mutants. The same phenotype is produced with all heterozygous pb alleles tested and is fully penetrant in two different ct mutant backgrounds. We show that this phenotype is accompanied by pronounced changes in the expression patterns of both ct and pb in labial discs. Furthermore, a significant proportion of ct mutant flies that are heterozygous for certain Antennapedia (Antp) alleles have thoracic defects that mimic loss-of-function Antp phenotypes, and ectopic expression of Cut in antennal discs results in ectopic Antp expression and a dominant Antp-like phenotype. Our results implicate ct in the regulation of expression and/or function of two homeotic genes and document a new role of ct in the control of segmental identity.

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Homeotic genes controlling flower development in Antirrhinum

Development ◽

10.1242/dev.113.supplement_1.149 ◽

1991 ◽

Vol 113 (Supplement_1) ◽

pp. 149-155

Author(s):

Enrico S. Coen ◽

Sandra Doyle ◽

Jose M. Romero ◽

Robert Elliott ◽

Ruth Magrath ◽

...

Keyword(s):

Flower Development ◽

Homeotic Genes ◽

Wild Type ◽

Developmental Pathway ◽

The Third ◽

Gene Functions ◽

Overlapping Domains ◽

Second Category ◽

Homeotic Mutations ◽

Primary Gene

In order to study genes controlling flower development, we have carried out an extensive transposon-mutagenesis experiment in Antirrhinum majus. More than 15 independent homeotic mutations were obtained, allowing three categories of genes to be defined. The first includes floricaula (flo), a primary gene required for the initiation of the floral developmental pathway. In the absence of the wild-type flo product, proliferating inflorescence meristems arise in place of flowers. The flo gene has been isolated and shown to be expressed transiently in a subset of organ primordia in the floral meristem. The second category includes genes that affect the identity, and also sometimes the number, of whorls of organs in the flower. These genes act in overlapping domains so that each whorl has a distinct combination of gene functions, suggesting a model for the genetic control of whorl identity and number. Genes of the third category control differences between organs In the same whorl and hence the overall symmetry of the flower. We discuss how the basic plan of the flower and inflorescence may arise through the interactions between the three categories of genes.

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Apoptosis – a death-inducing mechanism tightly linked with morphogenesis in Hydractina echinata (Cnidaria, Hydrozoa)

Development ◽

10.1242/dev.128.23.4891 ◽

2001 ◽

Vol 128 (23) ◽

pp. 4891-4898

Author(s):

Stefanie Seipp ◽

Jürgen Schmich ◽

Thomas Leitz

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Dna Fragmentation ◽

Temporal Pattern ◽

Turning Point ◽

Normal Development ◽

Body Parts ◽

Tissue Destruction ◽

Developmental Processes ◽

Developmental Program

Programmed cell death is not only known as a mechanism mediating tissue destruction, but also as an organismic tool for body shaping and regulation of morphological events during development. Here we report the tight and vital link of the most prominent form of programmed cell death, apoptosis, to one of the oldest, most basic, and most radical developmental processes, the metamorphosis of the marine hydrozoon Hydractinia echinata. Apoptosis, represented by DNA fragmentation, appears very early during metamorphosis, approximately 20 minutes post induction. It is then executed in a very distinct spatial and temporal pattern, including the removal or phagocytosis of a large number of larval cells prior to the appearance of stolons and tentacles. Our data indicate a developmental program striving to reduce all body parts that are no longer necessary, before reaching a distinct turning point, when the development of adult features is initiated. During these events, morphogenesis of basal and apical structures correlates with recycling of that particular larval region, indicated by the presence of apoptosis. Based on these data, the necessity of apoptosis for normal development of adult patterns is inferred and a fundamental association of apoptosis with developmental processes can be stated.

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Lymphoid expression and TATAA binding of a human protein containing an Antennapedia homeodomain

Blood ◽

10.1182/blood.v78.4.1047.1047 ◽

1991 ◽

Vol 78 (4) ◽

pp. 1047-1055 ◽

Cited By ~ 6

Author(s):

LJ Baier ◽

MC Hannibal ◽

EW Hanley ◽

GJ Nabel

Keyword(s):

Dna Binding ◽

B Cell ◽

Messenger Rna ◽

Binding Protein ◽

Homeobox Gene ◽

Lymphoid Cells ◽

Regulatory Function ◽

Homeotic Genes ◽

Expression Library ◽

Alternative Function

Abstract In an effort to identify human proteins that bind to the TATAA box, a lambda gt-11 expression library was screened with a radiolabeled DNA probe containing 12 copies of the TATAA sequence. A cDNA encoding a specific TATAA binding protein was isolated and found to contain a homeobox domain identical at 59 of 60 residues to the Drosophila Antennapedia (Antp) homeodomain, as well as another conserved motif found in homeotic genes, the homeo-specific pentapeptide. Although this and other Antp-like homeobox proteins have been described previously in neuronal cells and fibroblasts, we report the expression of this gene in lymphoid cells. This cDNA, isolated from a B-cell library, hybridizes to a 1.6-kb messenger RNA in several T- and B-cell lines, and the expected protein was identified in Jurkat T-lymphoid cells by Western blot analysis. The DNA binding specificity of this human Antp clone was analyzed using single-base mutations of the TATAA sequence. The first thymidine, as well as the last three bases (TAA), were important for homeobox binding. Finally, the function of the highly conserved homeospecific pentapeptide protein region was investigated in both the human and Drosophila Antp proteins. The homeospecific pentapeptide region was not required for DNA binding, and Drosophila Antp proteins mutated in the pentapeptide region were able to transactivate the Ubx promoter in Schneider L2 cells, in contrast to a homeodomain mutation, suggesting an alternative function for the homeospecific pentapeptide in homeotic genes. Because the human Antp TATAA binding protein is expressed in both lymphoid and non-lymphoid cells, we suggest that this homeobox gene has evolved a more general transcriptional regulatory function in higher eukaryotic cells.

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