The Drosophila 63F early puff contains E63-1, an ecdysone-inducible gene that encodes a novel Ca(2+)-binding protein

Development ◽  
1995 ◽  
Vol 121 (8) ◽  
pp. 2667-2679 ◽  
Author(s):  
A.J. Andres ◽  
C.S. Thummel
Keyword(s):  
Salivary Gland ◽  
Binding Protein ◽  
Polytene Chromosomes ◽  
Primary Response ◽  
Second Messenger Signaling ◽  
Additional Level ◽  
Inducible Genes ◽  
Early Puff ◽  
Inducible Gene

Pulses of ecdysone at the end of Drosophila larval development dramatically reprogram gene expression as they signal the onset of metamorphosis. Ecdysone directly induces several early puffs in the salivary gland polytene chromosomes that, in turn, activate many late puffs. Three early puffs, at 2B5, 74EF, and 75B, have been studied at the molecular level. Each contains a single ecdysone primary-response gene that encodes a family of widely expressed transcription factors. We report here a molecular characterization of the 63F early puff. Unexpectedly, we have found this locus to be significantly different from the previously characterized early puff loci. First, the 63F puff contains a pair of ecdysone-inducible genes that are transcribed in the larval salivary glands: E63-1 and E63-2. Second, E63-1 induction in late third instar larvae appears to be highly tissue-specific, restricted to the salivary gland. Third, E63-1 encodes a novel Ca(2+)-binding protein related to calmodulin. The discovery of an ecdysone-inducible Ca(2+)-binding protein provides a foundation for integrating steroid hormone and calcium second messenger signaling pathways and generates an additional level for potential regulation of the ecdysone response.

Genetic Analysis of the Drosophila 63F Early Puff: Characterization of Mutations in E63-1 and maggie, a Putative Tom22

Genetics ◽  
2000 ◽  
Vol 156 (1) ◽  
pp. 229-244
Author(s):  
Martina Vaskova ◽  
A M Bentley ◽  
Samantha Marshall ◽  
Pamela Reid ◽  
Carl S Thummel ◽  
...  
Keyword(s):  
Salivary Gland ◽  
Genetic Analysis ◽  
Polytene Chromosomes ◽  
Reading Frame ◽  
Protein Levels ◽  
Ef Hand ◽  
Larval Salivary Gland ◽  
Complementation Groups ◽  
Inducible Genes ◽  
Early Puff

Abstract The 63F early puff in the larval salivary gland polytene chromosomes contains the divergently transcribed E63-1 and E63-2 ecdysone-inducible genes. E63-1 encodes a member of the EF-hand family of Ca2+-binding proteins, while E63-2 has no apparent open reading frame. To understand the functions of the E63 genes, we have determined the temporal and spatial patterns of E63-1 protein expression, as well as undertaken a genetic analysis of the 63F puff. We show that E63-1 is expressed in many embryonic and larval tissues, but the third-instar larval salivary gland is the only tissue where increases in protein levels correlate with increases in ecdysone titer. Furthermore, the subcellular distribution of E63-1 protein changes dynamically in the salivary glands at the onset of metamorphosis. E63-1 and E63-2 null mutations, however, have no effect on development or fertility. We have characterized 40 kb of the 63F region, defined as the interval between Ubi-p and E63-2, and have identified three lethal complementation groups that correspond to the dSc-2, ida, and mge genes. We show that mge mutations lead to first-instar larval lethality and that Mge protein is similar to the Tom22 mitochondrial import proteins of fungi, suggesting that it has a role in mitochondrial function.

Isolation and characterization of fifteen ecdysone-inducible Drosophila genes reveal unexpected complexities in ecdysone regulation

1993 ◽  
Vol 13 (11) ◽  
pp. 7101-7111
Author(s):  
P Hurban ◽  
C S Thummel
Keyword(s):  
Salivary Gland ◽  
Steroid Hormone ◽  
Polytene Chromosomes ◽  
Feedback Regulation ◽  
Primary Response ◽  
Cdna Libraries ◽  
Isolation And Characterization ◽  
Larval Salivary Gland ◽  
Subtracted Cdna Libraries

Our insights into the regulatory mechanisms by which the steroid hormone ecdysone triggers Drosophila melanogaster metamorphosis have largely depended on puffs in the larval salivary gland polytene chromosomes as a means of identifying genes of interest. Here, we describe an approach that provides access to ecdysone-inducible genes that are expressed in most larval and imaginal tissues, regardless of their ability to form puffs in the polytene chromosomes. Several hundred cDNAs were picked at random from subtracted cDNA libraries and subjected to a rapid and sensitive screen for their ability to detect mRNAs induced by ecdysone in the presence of cycloheximide. Of the 15 genes identified in this manner, 2 correspond to early puffs in the salivary gland polytene chromosomes, at 63F and 75B, confirming that this screen functions at the desired level of sensitivity and is capable of identifying novel primary-response genes. Three of the genes, Eig45-1, Eig58, and Eig87, are expressed coordinately with the salivary gland early genes; one of them, Eig58, maps to the 58BC puff that is active when the 74EF and 75B early puffs are at their maximal size. Another gene identified in this screen, Eig17-1, encodes a novel cytochrome P-450. On the basis of its sequence identity and temporal profile of expression, this gene may play a role in steroid hormone metabolism and thus could provide a mechanism for feedback regulation of ecdysone production. Although all 15 genes have patterns of transcription that are consistent with ecdysone regulation in vivo, 5 genes do not appear to be induced by the late larval ecdysone pulse. This indicates that ecdysone induction in larval organs cultured with cycloheximide is not always indicative of a primary response to the hormone.

The Drosophila E74 gene is required for metamorphosis and plays a role in the polytene chromosome puffing response to ecdysone

Development ◽  
1995 ◽  
Vol 121 (5) ◽  
pp. 1455-1465 ◽  
Author(s):  
J.C. Fletcher ◽  
K.C. Burtis ◽  
D.S. Hogness ◽  
C.S. Thummel
Keyword(s):  
Gene Expression ◽  
Salivary Gland ◽  
Critical Role ◽  
Polytene Chromosomes ◽  
Transcription Unit ◽  
Loss Of Function ◽  
Phenotypic Analysis ◽  
Pupal Development ◽  
Puparium Formation ◽  
Early Puff

The steroid hormone ecdysone initiates Drosophila metamorphosis by reprogramming gene expression during late larval and prepupal development. The ecdysone-inducible gene E74, a member of the ets proto-oncogene family, has been proposed to play a key role in this process. E74 is encoded within the 74EF early puff and consists of two overlapping transcription units, E74A and E74B. To assess the function(s) of E74 during metamorphosis, we have isolated and characterized recessive loss-of-function mutations specific to each transcription unit. We find that mutations in E74A and E74B are predominantly lethal during prepupal and pupal development, consistent with a critical role for their gene products in metamorphosis. Phenotypic analysis reveals that E74 function is required for both pupariation and pupation, and for the metamorphosis of both larval and imaginal tissues. E74B mutants are defective in puparium formation and head eversion and die as prepupae or cryptocephalic pupae, while E74A mutants pupariate normally and die either as prepupae or pharate adults. We have also investigated the effects of the E74 mutations on gene expression by examining the puffing pattern of the salivary gland polytene chromosomes in newly formed mutant prepupae. Most puffs are only modestly affected by the E74B mutation, whereas a subset of late puffs are sub-maximally induced in E74A mutant prepupae. These observations are consistent with Ashburner's proposal that early puff proteins induce the formation of late puffs, and define E74A as a regulator of late puff activity. They also demonstrate that E74 plays a wide role in reshaping the insect during metamorphosis, affecting tissues other than the salivary gland in which it was originally identified.

Description of Chironomus quinnitukut, n. sp., closely related tothe C. decorus group in North America, with characterization of an additional larval form from halobiontic habitats

Zootaxa ◽  
2019 ◽  
Vol 2716 (1) ◽  
pp. 29 ◽  
Author(s):  
JON MARTIN ◽  
JAMES E. SUBLETTE ◽  
BROUGHTON A. CALDWELL
Keyword(s):  
Salivary Gland ◽  
North America ◽  
Banding Pattern ◽  
Polytene Chromosomes ◽  
Cape Cod ◽  
Life Stages ◽  
Larval Morphology ◽  
Larval Form

Chironomus quinnitukqut n. sp., from halobiontic habitats in Connecticut and Massachusetts, is described on the basis of the adult and larval morphology, and the banding pattern of the salivary gland chromosomes. In previous studies, the Connecticut population has been referred to as Chironomus atrella Townes, but a re-examination has indicated that it can be readily differentiated from C. atrella in all life stages. Rather, the banding pattern of the polytene chromosomes indicates the species, is best placed as a member of the Chironomus decorus group. Larvae of a second halobiontic species, C. species Cape Cod, are morphologically very similar to C. quinnitukqut and this species also appears to be a member of the C. decorus group.

Molecular characterization of a novel salt-inducible gene for an OSBP (oxysterol-binding protein)-homologue from soybean

Gene ◽  
2008 ◽  
Vol 407 (1-2) ◽  
pp. 12-20 ◽  
Author(s):  
Dong Yan Li ◽  
Hayami Inoue ◽  
Masayuki Takahashi ◽  
Toshio Kojima ◽  
Masakazu Shiraiwa ◽  
...  
Keyword(s):  
Molecular Characterization ◽  
Binding Protein ◽  
Oxysterol Binding Protein ◽  
Inducible Gene

scholarly journals Isolation and characterization of fifteen ecdysone-inducible Drosophila genes reveal unexpected complexities in ecdysone regulation.

1993 ◽  
Vol 13 (11) ◽  
pp. 7101-7111 ◽  
Author(s):  
P Hurban ◽  
C S Thummel
Keyword(s):  
Salivary Gland ◽  
Steroid Hormone ◽  
Polytene Chromosomes ◽  
Feedback Regulation ◽  
Primary Response ◽  
Cdna Libraries ◽  
Isolation And Characterization ◽  
Larval Salivary Gland ◽  
Subtracted Cdna Libraries

Our insights into the regulatory mechanisms by which the steroid hormone ecdysone triggers Drosophila melanogaster metamorphosis have largely depended on puffs in the larval salivary gland polytene chromosomes as a means of identifying genes of interest. Here, we describe an approach that provides access to ecdysone-inducible genes that are expressed in most larval and imaginal tissues, regardless of their ability to form puffs in the polytene chromosomes. Several hundred cDNAs were picked at random from subtracted cDNA libraries and subjected to a rapid and sensitive screen for their ability to detect mRNAs induced by ecdysone in the presence of cycloheximide. Of the 15 genes identified in this manner, 2 correspond to early puffs in the salivary gland polytene chromosomes, at 63F and 75B, confirming that this screen functions at the desired level of sensitivity and is capable of identifying novel primary-response genes. Three of the genes, Eig45-1, Eig58, and Eig87, are expressed coordinately with the salivary gland early genes; one of them, Eig58, maps to the 58BC puff that is active when the 74EF and 75B early puffs are at their maximal size. Another gene identified in this screen, Eig17-1, encodes a novel cytochrome P-450. On the basis of its sequence identity and temporal profile of expression, this gene may play a role in steroid hormone metabolism and thus could provide a mechanism for feedback regulation of ecdysone production. Although all 15 genes have patterns of transcription that are consistent with ecdysone regulation in vivo, 5 genes do not appear to be induced by the late larval ecdysone pulse. This indicates that ecdysone induction in larval organs cultured with cycloheximide is not always indicative of a primary response to the hormone.

Detection and characterization of a heat and acid stable progesterone binding protein in the rat lung

1984 ◽  
Vol 104 (4_Supplb) ◽  
pp. S91-S92
Author(s):  
G. DAXENBICHLER ◽  
E. H. MOSER
Keyword(s):  
Binding Protein ◽  
Rat Lung ◽  
Acid Stable
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