Linkage and evolutionary diversification of developmentally regulated multigene families: tandem arrays of the 401/18 chorion gene pair in silkmoths.

The coordinately expressed silkmoth chorion genes, 401 and 18, are closely linked as a pair, in divergent orientation. Analysis of overlapping clones (chromosomal "walk") demonstrated that each of the multiple copies of this gene pair is embedded within a larger deoxyribonucleic acid unit, which is tandemly repeated in a few arrays or possibly a single array. Southern analysis and examination of clones from a single individual moth demonstrated that the repeat units are extensively polymorphic in restriction sites, length, and possibly number, no differential amplification was evident during choriogenesis. Intron and 5'-flanking sequences were shown to be specific for the 401/18 gene pair and not to be present elsewhere in the genome. The spatial distribution of variations in the genes and their flanking sequences were examined.

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Glycoproteins that exhibit extensive size polymorphisms in Dictyostelium discoideum.

Genetics ◽

10.1093/genetics/122.1.59 ◽

1989 ◽

Vol 122 (1) ◽

pp. 59-64 ◽

Cited By ~ 2

Author(s):

E Smith ◽

A A Gooley ◽

G C Hudson ◽

K L Williams

Keyword(s):

Linkage Group ◽

Dictyostelium Discoideum ◽

Allelic Variation ◽

Surface Glycoprotein ◽

Developmentally Regulated ◽

Electrophoretic Variants ◽

Cellular Slime Mould ◽

Repeat Units ◽

Group I ◽

Cellular Slime

Abstract Electrophoretic variants which arise from amino acid substitutions, leading to charge differences between proteins are ubiquitous and have been used extensively for genetic analysis. Less well documented are polymorphisms in the size of proteins. Here we report that a group of glycoproteins, which share a common carbohydrate epitope, vary in size in different isolates of the cellular slime mould, Dictyostelium discoideum. One of these proteins, PsA, a developmentally regulated prespore-specific surface glycoprotein, has previously been shown to exist in three size forms due to allelic variation at the pspA locus on linkage group I. In this report, a second glycoprotein, PsB, which is also prespore specific but found inside prespore cells, is studied. PsB maps to linkage group II and exhibits at least four different sizes in the isolates examined. We propose that the size polymorphisms are the product of allelic variation at the pspB locus, due to differences in the number of repeat units.

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Synergistic interactions of silkmoth chorion promoter-binding factors.

Molecular and Cellular Biology ◽

10.1128/mcb.11.4.1954 ◽

1991 ◽

Vol 11 (4) ◽

pp. 1954-1964 ◽

Cited By ~ 19

Author(s):

Y A Skeiky ◽

K Iatrou

Keyword(s):

Cell Line ◽

Transcriptional Activation ◽

Transcriptional Repression ◽

Specific Binding ◽

Ovarian Tissue ◽

Mobility Shift ◽

Minimum Requirement ◽

Synergistic Interactions ◽

Chorion Genes ◽

Silkmoth Chorion

Two DNA-binding proteins, BCFI and BCFII, that interact with defined promoter sequences of silkmoth chorion genes of late developmental specificity appear in the nuclei of follicular cells at a time that coincides with the transcriptional activation of the corresponding genes. BCFI prebinding is shown to be indispensable for stable binding of BCFII to its cognate sequence. BCFI and BCFII synergism requires a relatively stringent stereospecific alignment and is a prerequisite for the assembly of higher-order protein-promoter DNA complexes containing additional factors, which are neither gene (stage) nor class (chorion) specific. Binding of BCFI to its site correlates with the induction of DNA structural perturbations that may facilitate assembly of additional factors on the promoter. The BCFI-binding domain contains a core hexanucleotide sequence, AGATAA, which represents the major binding determinant of the erythroid-specific transcription factor GATA-1 of higher vertebrates. This sequence is shown to be necessary and sufficient for binding of BCFI, as it is for a factor that is present in induced K562 human erythroleukemic cells, presumably GATA-1. Comparative analyses of mobility shift patterns obtained with partially proteolyzed preparations of these two unrelated factors were used to confirm that a BCFI-like chorion promoter-binding protein, which is present in the nuclei of an established silkmoth cell line derived from ovarian tissue, is in fact BCFI. The transcriptional repression of endogenous chorion genes in this cell line coupled with the documented absence of factor BCFII suggests that the synergistic interactions between these two factors constitute a minimum requirement for late chorion gene expression.

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Temporal and spatial expression patterns of the small heat shock (hsp16) genes in transgenic Caenorhabditis elegans.

Molecular Biology of the Cell ◽

10.1091/mbc.3.2.221 ◽

1992 ◽

Vol 3 (2) ◽

pp. 221-233 ◽

Cited By ~ 199

Author(s):

E G Stringham ◽

D K Dixon ◽

D Jones ◽

E P Candido

Keyword(s):

Caenorhabditis Elegans ◽

Heat Shock ◽

Gene Pair ◽

Expression Patterns ◽

Developmentally Regulated ◽

Noncoding Sequences ◽

C Elegans ◽

Gene Pairs ◽

Temporal And Spatial ◽

Beta Galactosidase

The expression of the hsp16 gene family in Caenorhabditis elegans has been examined by introducing hsp16-lacZ fusions into the nematode by transformation. Transcription of the hsp16-lacZ transgenes was totally heat-shock dependent and resulted in the rapid synthesis of detectable levels of beta-galactosidase. Although the two hsp16 gene pairs of C. elegans are highly similar within both their coding and noncoding sequences, quantitative and qualitative differences in the spatial pattern of expression between gene pairs were observed. The hsp16-48 promoter was shown to direct greater expression of beta-galactosidase in muscle and hypodermis, whereas the hsp16-41 promoter was more efficient in intestine and pharyngeal tissue. Transgenes that eliminated one promoter from a gene pair were expressed at reduced levels, particularly in postembryonic stages, suggesting that the heat shock elements in the intergenic region of an hsp16 gene pair may act cooperatively to achieve high levels of expression of both genes. Although the hsp16 gene pairs are never constitutively expressed, their heat inducibility is developmentally restricted; they are not heat inducible during gametogenesis or early embryogenesis. The hsp16 genes represent the first fully inducible system in C. elegans to be characterized in detail at the molecular level, and the promoters of these genes should find wide applicability in studies of tissue- and developmentally regulated genes in this experimental organism.

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Genome organization of the Chelonus inanitus polydnavirus: excision sites, spacers and abundance of proviral and excised segments

Journal of General Virology ◽

10.1099/vir.0.82396-0 ◽

2007 ◽

Vol 88 (2) ◽

pp. 450-457 ◽

Cited By ~ 36

Author(s):

Marc Annaheim ◽

Beatrice Lanzrein

Keyword(s):

Symbiotic Association ◽

Opposite Orientation ◽

Double Stranded Dna ◽

Circular Segment ◽

Multiple Copies ◽

Flanking Sequences ◽

Terminal Repeats ◽

First Time ◽

Segmented Genome ◽

Combined Data

Polydnaviruses are only found in symbiotic association with parasitic wasps within the families Ichneumonidae and Braconidae (ichnoviruses and bracoviruses). They have a segmented genome consisting of circular double-stranded DNA. In the proviral linear form they are integrated in the wasp's genome; in two bracoviruses, segments were found to be clustered. Proviral segments have direct terminal repeats. Segment excision has been proposed to occur through juxtaposition of these repeats by formation of a loop and recombination; one copy of the repeat then ends up in the circular segment and one in the rejoined DNA. Here we analysed the excision/circularization site of four segments of the Chelonus inanitus bracovirus (CiV) and found that they are similar to the two already known sites; on the basis of the combined data an extended excision site motif was found. Analyses of segment flanking sequences led to the first identification of one complete and several partial spacers between proviral segments in a polydnavirus. The spacer between the proviral segments CiV14 and CiV22.5 has a length of 2065 bp; the terminal repeats of CiV14 and CiV22.5 were seen to have an opposite orientation and from this a model on the spacial organization of the loops of the proviral cluster is proposed. Through various approaches it was shown that spacers are not excised or injected into the host. Measurement of relative abundances of various segments in proviral and excised form indicates for the first time that abundant segments are present in multiple copies in the proviral form.

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The Drosophila ACE3 chorion element autonomously induces amplification.

Molecular and Cellular Biology ◽

10.1128/mcb.12.5.2444 ◽

1992 ◽

Vol 12 (5) ◽

pp. 2444-2453 ◽

Cited By ~ 17

Author(s):

J L Carminati ◽

C G Johnston ◽

T L Orr-Weaver

Keyword(s):

Dna Replication ◽

Dna Sequences ◽

Regulatory Elements ◽

P Element ◽

Follicle Cells ◽

Control Element ◽

The Third ◽

Transposon Insertion ◽

Multiple Copies ◽

Flanking Sequences

The Drosophila chorion genes amplify in the follicle cells by repeated rounds of reinitiation of DNA replication. ACE3 (amplification control element from the third chromosome) has been identified by a series of deletion experiments as an important control element for amplification of the third-chromosome chorion cluster. Several elements that quantitatively enhance amplification also have been defined. We show that a single 440-bp ACE3 sequence is sufficient to regulate amplification with proper developmental specificity autonomously from other chorion DNA sequences and regulatory elements. Although ACE3 is sufficient for amplification, the levels of amplification are low even when ACE3 is present in multiple copies. When controlled solely by ACE3, amplification initiates either at ACE3 or within closely linked sequences. Amplification of an ACE3 transposon insertion produces a gradient of amplified DNA that extends into flanking sequences approximately the same distance as does the amplification gradient at the endogenous chorion locus. The profile and extent of the amplified gradient imply that the low levels of amplification observed are the result of limited rounds of initiation of DNA replication. Transposon inserts containing multiple copies of ACE3 in a tandem, head-to-tail array are maintained stably in the chromosome. However, mobilization of the P-element transposons containing ACE3 multimers results in deletions within the array at a high frequency.

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Intracisternal A-particle genes in Mus musculus: a conserved family of retrovirus-like elements

Molecular and Cellular Biology ◽

10.1128/mcb.1.3.216-227.1981 ◽

1981 ◽

Vol 1 (3) ◽

pp. 216-227

Author(s):

E L Kuff ◽

L A Smith ◽

K K Lueders

Keyword(s):

Mus Musculus ◽

Ribonucleic Acid ◽

Deoxyribonucleic Acid ◽

Restriction Site ◽

Lambda Phage ◽

Base Pairs ◽

Restriction Sites ◽

Flanking Sequences ◽

Specific Restriction ◽

Intracisternal A Particle

The structural organization of intracisternal A-particle genes has been studied, using isolates from a mouse gene library in lambda phage Charon 4A. The predominant gene form among the isolates was 7.3 kilobases (kb) in length. R-loops between the 7-kb (35S) A-particle genomic ribonucleic acid and several of these genes were colinear, with no visible evidence of intervening deoxyribonucleic acid sequences. One recombinant was found with an A-particle gene that contained a 1.7-kb deletion. Using the deletion as a reference, the deoxyribonucleic acid and ribonucleic acid homology regions were localized with respect to one another and to the restriction map: the 5' terminus of the ribonucleic acid was several hundred base pairs within the 5' end of the deoxyribonucleic acid homology region. Restriction endonuclease fragments encompassing the 5' and 3' regions of one 7.3-kb gene were separately subcloned into pBR322. Heteroduplexes between the two subclones revealed an approximately 300-base pair segment of terminally redundant sequences. The cloned 3' fragment hybridized with restriction fragments from the 5' end of several other A-particle genes, demonstrating the presence of common (though not necessarily identical) terminally repeated sequences. A-particle genes varied in the occurrence of specific restriction sites at characteristic internal loci. However, heteroduplexes between several variant 7.3-kb genes showed continuous homology regions even when spread under stringent hybridization conditions. The relative abundance of restriction site variants was highly conserved in 12 laboratory strains of Mus musculus, in embryonic and adult tissues of a single inbred strain, and in the SC-1 cell line of feral mouse origin, but appeared to differ in a feral Japanese substrain, Mus musculus molossinus. Some evidence suggests that subsets of A-particle genes may have similar flanking sequences. The results are discussed in terms of the evolution of this multigene family.

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Organization of regionally expressed silkmoth chorion genes

Molecular and Cellular Biology ◽

10.1128/mcb.6.9.3215-3220.1986 ◽

1986 ◽

Vol 6 (9) ◽

pp. 3215-3220

Author(s):

A K Hatzopoulos ◽

J C Regier

Keyword(s):

Gene Expression ◽

Follicle Cells ◽

Gene Copy ◽

Late Period ◽

Chorion Genes ◽

Copy Numbers ◽

Total Dna ◽

Dna Strand ◽

Gene Copy Numbers ◽

Silkmoth Chorion

We described the organization of two silkmoth chorion genes, called E1 and E2, whose expression is largely restricted in time to the very late period of choriogenesis and in space to one of two major subpopulations of follicle cells. Using E1 and E2 clone cDNAs as probes, we showed that gene copy numbers per haploid genome remain constant throughout silkmoth development despite major changes in total DNA content per nucleus. Furthermore, gene copy numbers are the same in both cellular regions of the choriogenic follicle despite differences in nuclear size and levels of E gene expression. Southern analysis indicated between two and four copies each for E1 and E2 genes. Analysis of chromosomal clones showed that single copies of E1 and E2 are separated by about 7.5 kilobases and are transcribed from the same DNA strand. Two distinct pairs of cloned E1 and E2 genes were characterized. No other chorion genes were in their immediate vicinity.

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Synergistic interactions of silkmoth chorion promoter-binding factors

Molecular and Cellular Biology ◽

10.1128/mcb.11.4.1954-1964.1991 ◽

1991 ◽

Vol 11 (4) ◽

pp. 1954-1964

Author(s):

Y A Skeiky ◽

K Iatrou

Keyword(s):

Cell Line ◽

Transcriptional Activation ◽

Transcriptional Repression ◽

Specific Binding ◽

Ovarian Tissue ◽

Mobility Shift ◽

Minimum Requirement ◽

Synergistic Interactions ◽

Chorion Genes ◽

Silkmoth Chorion

Two DNA-binding proteins, BCFI and BCFII, that interact with defined promoter sequences of silkmoth chorion genes of late developmental specificity appear in the nuclei of follicular cells at a time that coincides with the transcriptional activation of the corresponding genes. BCFI prebinding is shown to be indispensable for stable binding of BCFII to its cognate sequence. BCFI and BCFII synergism requires a relatively stringent stereospecific alignment and is a prerequisite for the assembly of higher-order protein-promoter DNA complexes containing additional factors, which are neither gene (stage) nor class (chorion) specific. Binding of BCFI to its site correlates with the induction of DNA structural perturbations that may facilitate assembly of additional factors on the promoter. The BCFI-binding domain contains a core hexanucleotide sequence, AGATAA, which represents the major binding determinant of the erythroid-specific transcription factor GATA-1 of higher vertebrates. This sequence is shown to be necessary and sufficient for binding of BCFI, as it is for a factor that is present in induced K562 human erythroleukemic cells, presumably GATA-1. Comparative analyses of mobility shift patterns obtained with partially proteolyzed preparations of these two unrelated factors were used to confirm that a BCFI-like chorion promoter-binding protein, which is present in the nuclei of an established silkmoth cell line derived from ovarian tissue, is in fact BCFI. The transcriptional repression of endogenous chorion genes in this cell line coupled with the documented absence of factor BCFII suggests that the synergistic interactions between these two factors constitute a minimum requirement for late chorion gene expression.

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