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C S Gillmor

Publications and source records attributed to C S Gillmor.

6 recordsLinked to original sources

VACUOLELESS1 is an essential gene required for vacuole formation and morphogenesis in Arabidopsis.

Most plant cells are characterized by the presence of a large central vacuole that in differentiated cells accounts for more than 90% of the total volume. We have undertaken a genetic screen to look for mutants that are affected in the formation of vacuoles in plants. In this study, we report that inactivation of the Arabidopsis gene VACUOLELESS1 (VCL1) blocks vacuole formation and alters the pattern of cell division orientation and cell elongation in the embryo. Consistent with a role in vacuole biogenesis, we show that VCL1 encodes the Arabidopsis ortholog of yeast Vps16p. In contrast to yeast mutants that lack a vacuolar compartment but are viable and morphologically normal, loss of the plant vacuole leads to aberrant morphogenesis and embryonic lethality.

Alleles↗

Positional cloning in Arabidopsis. Why it feels good to have a genome initiative working for you.

Positional (or map-based) cloning techniques are widely used to identify the protein products of genes defined by mutation. In Arabidopsis the information generated by the Genome Initiative is giving this approach a decisive boost. A wealth of sequence polymorphisms and molecular markers is now available and can be exploited for fine mapping with technically simple and robust polymerase chain reaction-based methods. As a result it has become possible to complete positional cloning projects in a short time and with relatively little effort.

Arabidopsis↗

EMB30 is essential for normal cell division, cell expansion, and cell adhesion in Arabidopsis and encodes a protein that has similarity to Sec7.

The EMB30 gene is involved in apical-basal pattern formation in the Arabidopsis embryo. Mutations in this locus produce mutants with a wide range of seedling phenotypes, but all of the mutants lack a root and a true hypocotyl. We have cloned the EMB30 gene, and it encodes a protein that has similarity to the yeast Sec7 protein and to two other open reading frames identified in clones from humans and C. elegans. We refer to the region of similarity among these four sequences as the Sec7 domain. The emb30-1 allele has a mutation in the Sec7 domain that alters a residue conserved in all four of these sequences, suggesting that this domain may be important for EMB30 function. Molecular data and microscopy studies of emb30 seedlings presented here indicate that EMB30 affects cell division, elongation, and adhesion and functions in seedling and adult plants as well as during embryogenic pattern formation.

Amino Acid Sequence↗

Further remarks concerning visual images observed following unilateral enucleation.

Following an earlier report, the article offers additional points concerning visual images observed after enucleation. These concern: (i) the relationship between field-cut due to the lesion before surgery and corresponding blank areas within the post-enucleation images; (ii) similarities in motion between the foveal images and foveally-fixated afterimages; (iii) possible correspondence of time course of the images to transneuronal atrophy and cell loss in human and monkey studies.

Afterimage↗

Visual images observed following an enucleation.

After enucleation of the right eye the author observed persistent and continuous visual images featuring angular groups of parallel-line segments which have continued for two years, to the present time, though considerably diminished. These phenomena are reported along with results of measurements of the images and of several simple experiments. Some quantitative comparisions are made to results from studies of macaque monkeys, and to human migraine fortification images.

Adult↗