malan: MAle Lineage ANalysis

Abstract Main conclusion Inducible lineage analysis and cell ablation via conditional toxin expression in cells expressing the DORNRÖSCHEN-LIKE transcription factor represent an effective and complementary adjunct to conventional methods of functional gene analysis. Abstract Classical methods of functional gene analysis via mutational and expression studies possess inherent limitations, and therefore, the function of a large proportion of transcription factors remains unknown. We have employed two complementary, indirect methods to obtain functional information for the AP2/ERF transcription factor DORNRÖSCHEN-LIKE (DRNL), which is dynamically expressed in flowers and marks lateral organ founder cells. An inducible, two-component Cre–Lox system was used to express beta-glucuronidase GUS in cells expressing DRNL, to perform a sector analysis that reveals lineages of cells that transiently expressed DRNL throughout plant development. In a complementary approach, an inducible system was used to ablate cells expressing DRNL using diphtheria toxin A chain, to visualise the phenotypic consequences. These complementary analyses demonstrate that DRNL functionally marks founder cells of leaves and floral organs. Clonal sectors also included the vasculature of the leaves and petals, implicating a previously unidentified role for DRNL in provasculature development, which was confirmed in cotyledons by closer analysis of drnl mutants. Our findings demonstrate that inducible gene-specific lineage analysis and cell ablation via conditional toxin expression represent an effective and informative adjunct to conventional methods of functional gene analysis.

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Major sex-determining genes and the control of sexual dimorphism in Caenorhabditis elegans

Genome ◽

10.1139/g89-116 ◽

1989 ◽

Vol 31 (2) ◽

pp. 625-637 ◽

Cited By ~ 4

Author(s):

Jonathan Hodgkin ◽

Andrew D. Chisholm ◽

Michael M. Shen

Keyword(s):

Caenorhabditis Elegans ◽

Sex Determination ◽

X Chromosome ◽

Germ Line ◽

Cell Lineage ◽

Regulatory Genes ◽

Nematode Caenorhabditis Elegans ◽

X Chromosomes ◽

The Many ◽

Lineage Analysis

Sex determination in Caenorhabditis elegans involves a cascade of major regulatory genes connecting the primary sex determining signal, X chromosome dosage, to key switch genes, which in turn direct development along either male or female pathways. Animals with one X chromosome (XO) are male, while animals with two X chromosomes (XX) are hermaphrodite: hermaphrodite development occurs because the action of the regulatory genes is modified in the germ line so that both sperm and oocytes are made inside a completely female soma. The regulatory genes are being examined by both genetic and molecular means. We discuss how these major genes, in particular the last switch gene in the cascade, tra-1, might regulate the many different sex-specific events that occur during the development of the hermaphrodite and of the male.Key words: nematode, Caenorhabditis elegans, sex determination, sexual differentiation, cell lineage analysis.

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Cell lineage of homeotic mutants of Drosophila

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1985.0183 ◽

1985 ◽

Vol 312 (1153) ◽

pp. 139-144 ◽

Cited By ~ 1

Keyword(s):

Mode Of Action ◽

Cell Lineage ◽

Precursor Cells ◽

Larval Period ◽

Homeotic Genes ◽

Lineage Analysis

The homeotic genes specify the development of specific groups of precursor cells. They establish the correct state of determination of the different primordia. Cell lineage analysis has been particularly useful in studying the mode of action of homeotic genes. The main findings are: (i) most, perhaps all, the homeotic genes are required by every cell of the corresponding primordium (that is, they are cell autonomous); (ii) they act on anatomical units defined by compartment boundaries and including one or more compartments, (iii) most, but not all, homeotic genes are required until the end of the larval period; (iv) the homeotic genes act in combination so that the appropriate development of a given primordium may be established by the contribution of several homeotic genes.

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Cell lineage analysis in neural crest ontogeny

Journal of Neurobiology ◽

10.1002/neu.480240203 ◽

1993 ◽

Vol 24 (2) ◽

pp. 146-161 ◽

Cited By ~ 74

Author(s):

Nicole M. Le Douarin ◽

Elisabeth Dupin

Keyword(s):

Neural Crest ◽

Cell Lineage ◽

Lineage Analysis

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Genetic analysis of leaf development in cotton

Development ◽

10.1242/dev.113.supplement_1.39 ◽

1991 ◽

Vol 113 (Supplement_1) ◽

pp. 39-46 ◽

Cited By ~ 1

Author(s):

Liam Dolan ◽

R. Scott Poethig

Keyword(s):

Leaf Growth ◽

Leaf Shape ◽

Cell Lineage ◽

Cotton Leaf ◽

Expansion Phase ◽

Genetic Mosaics ◽

Developmental Age ◽

Allometric Analysis ◽

Marginal Region ◽

Lineage Analysis

Leaf shape in cotton is regulated by the developmental age of the shoot and by several major genes that affect leaf lobing. The effect of these factors was investigated by allometric analysis, cell lineage analysis, and by studying the expression of the leaf shape mutation, Okra, in genetic mosaics. Allometric analysis of leaf growth suggests that leaf shape is determined during the initiation of the primordium rather than during the expansion phase of leaf growth. Clonal analysis demonstrates that both the rate and duration of cell division are fairly uniform throughout the leaf. Cells in the marginal region of the developing cotton leaf contribute more to the growth of the lamina than they do in tobacco. The Okra mutation acts early in the development of a leaf and appears to accentuate a developmental pattern that is also responsible for heteroblastic variation in leaf shape. The expression of this mutation in genetic mosaics demonstrates that its effect does not diffuse laterally within the leaf primordium.

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