The Arabidopsis Information Resource (TAIR): a comprehensive database and web-based information retrieval, analysis, and visualization system for a model plant.

Arabidopsis thaliana, a small annual plant belonging to the mustard family, is the subject of study by an estimated 7000 researchers around the world. In addition to the large body of genetic, physiological and biochemical data gathered for this plant, it will be the first higher plant genome to be completely sequenced, with completion expected at the end of the year 2000. The sequencing effort has been coordinated by an international collaboration, the Arabidopsis Genome Initiative (AGI). The rationale for intensive investigation of Arabidopsis is that it is an excellent model for higher plants. In order to maximize use of the knowledge gained about this plant, there is a need for a comprehensive database and information retrieval and analysis system that will provide user-friendly access to Arabidopsis information. This paper describes the initial steps we have taken toward realizing these goals in a project called The Arabidopsis Information Resource (TAIR) (www.arabidopsis.org).

Shoot meristem size is dependent on inbred background and presence of the maize homeobox gene, knotted1.

The knotted1 (kn1) gene of maize is expressed in meristems and is absent from leaves, including the site of leaf initiation within the meristem. Recessive mutations of kn1 have been described that limit the capacity to make branches and result in extra carpels. Dominant mutations suggest that kn1 function plays a role in maintaining cells in an undifferentiated state. We took advantage of a Ds-induced dominant allele in order to screen for additional recessive alleles resulting from mobilization of the Ds element. Analysis of one such allele revealed a novel embryonic shoot phenotype in which the shoot initiated zero to few organs after the cotyledon was made, resulting in plants that arrested as seedlings. We refer to this phenotype as a limited shoot. The limited shoot phenotype reflected loss of kn1 function, but its penetrance was background dependent. We examined meristem size and found that plants lacking kn1 function had shorter meristems than non-mutant siblings. Furthermore, meristems of restrictive inbreds were significantly shorter than meristems of permissive inbreds, implying a correlation between meristem height and kn1 gene function in the embryo. Analysis of limited shoot plants during embryogenesis indicated a role for kn1 in shoot meristem maintenance. We discuss a model for kn1 in maintenance of the morphogenetic zone of the shoot apical meristem.

Knots in the family tree: evolutionary relationships and functions of knox homeobox genes.

Knotted-like homeobox (knox) genes constitute a gene family in plants. Class I knox genes are expressed in shoot apical meristems, and (with notable exceptions) not in lateral organ primordia. Class II genes have more diverse expression patterns. Loss and gain of function mutations indicate that knox genes are important regulators of meristem function. Gene duplication has contributed to the evolution of families of homeodomain proteins in metazoans. We believe that similar mechanisms have contributed to the diversity of knox gene function in plants. Knox genes may have contributed to the evolution of compound leaves in tomato and could be involved in the evolution of morphological traits in other species. Alterations in cis-regulatory regions in some knox genes correlate with novel patterns of gene expression and distinctive morphologies. Preliminary data from the analysis of class I knox gene expression illustrates the evolution of complex patterns of knox expression is likely to have occurred through loss and gain of domains of gene expression.

The AINTEGUMENTA gene of Arabidopsis required for ovule and female gametophyte development is related to the floral homeotic gene APETALA2.

Ovules play a central role in plant reproduction, generating the female gametophyte within sporophytic integuments. When fertilized, the integuments differentiate into the seed coat and support the development of the embryo and endosperm. Mutations in the AINTEGUMENTA (ANT) locus of Arabidopsis have a profound effect on ovule development. Strong ant mutants have ovules that fail to form integuments or a female gametophyte. Flower development is also altered, with a random reduction of organs in the outer three whorls. In addition, organs present in the outer three floral whorls often have abnormal morphology. Ovules from a weak ant mutant contain both inner and outer integuments but generally fail to produce a functional female gametophyte. We isolated the ANT gene by using a mutation derived by T-DNA insertional mutagenesis. ANT is a member of a gene family that includes the floral homeotic gene APETALA2 (AP2). Like AP2, ANT contains two AP2 domains homologous with the DNA binding domain of ethylene response element binding proteins. ANT is expressed most highly in developing flowers but is also expressed in vegetative tissue. Taken together, these results suggest that ANT is a transcription factor that plays a critical role in regulating ovule and female gametophyte development.

The BELL1 gene encodes a homeodomain protein involved in pattern formation in the Arabidopsis ovule primordium.

Ovule development in Arabidopsis involves the formation of three morphologically defined proximal-distal pattern elements. Integuments arise from the central pattern element. Analysis of Bell 1 (Bel 1) mutant ovules indicated that BEL1 was required for integument development. Cloning of the BEL1 locus reveals that it encodes a homeodomain transcription factor. Prior to integument initiation, BEL1 RNA localizes to the central domain, providing molecular evidence for a central pattern element. Therefore, proximal-distal patterning of the ovule involves the regulated expression of the BEL1 gene that controls integument morphogenesis. A model for BEL1 function is evaluated with regard to new data showing the expression pattern of the floral homeotic gene AGAMOUS (AG) early in wild-type and BEL1 ovule development.

Homeotic Transformation of Ovules into Carpel-like Structures in Arabidopsis.

Ovules are specialized reproductive organs that develop within the carpels of higher plants. In Arabidopsis, mutations in two genes, BELL1 (BEL1) and APETALA2 (AP2), disrupt ovule development. In Bel1 ovules, the inner integument fails to form, the outer integument develops abnormally, and the embryo sac arrests at a late stage of megagametogenesis. During later stages of ovule development, cells of the outer integument of a Bel1 ovule sometimes develop into a carpel-like structure with stigmatic papillae and second-order ovules. The frequency of carpel-like structures was highest when plants were grown under conditions that normally induced flowering and was correlated with ectopic expression in the ovule of AGAMOUS (AG), an organ-identity gene required for carpel formation. Together, these results suggested that BEL1 negatively regulates AG late in ovule development. Likewise, mutants homozygous for the strong AP2 allele ap2-6 sometimes displayed structures with carpel-like features in place of ovules. However, such abnormal Ap2 ovules are much less ovulelike in morphology and form earlier than the Bel1 carpel-like structures. Because one role of the AP2 gene is to negatively regulate AG expression early in flower development, it is possible that AP2 works in a similar manner in the ovule. A novel ovule phenotype observed in Bel1/Ap2-6 double mutants suggested that BEL1 and AP2 genes function independently during ovule development.

Remembered childhood artifacts. Windows to the past.

This paper explores how working with memories of childhood songs, pictures, poems, and stories can facilitate and deepen the analytic process. These artifacts are special metaphors for networks of repressed memories, in many respects like dream images. But unlike dream images and other early memories, they exist in the real world and can be verified. They provide the child with a scaffolding upon which to build a version of reality, putting conflictual situations into words, melodies, and images, and organize representations of relationships and affect that remain internally alive and can be reworked in unconscious fantasy. Three clinical examples illustrate how such associations enable the analysand to express ways in which the present, including the transference, is linked with the past.

Beginning careers in academic psychiatry for women--"Bermuda Triangle"?

OBJECTIVE: The proportion of women in leadership positions in academic psychiatry has not kept pace with the increase in the number of women entering the field. This study examines differences in career activities between women and men who graduated from the Yale University psychiatric residency training program and explores whether these differences can be explained by preresidency expectations, residency experiences, or training immediately after residency. METHOD: Departmental educational records of the Yale residency program were reviewed to determine professional interests expressed before psychiatric residency and training focus during residency for 355 residents in the 1970-1983 graduating classes. A 1984 follow-up study focused on their postresidency career activities. Differences in preresidency interests and experiences, training activities, and career paths between all female and male graduates and between women and men who chose academic careers were examined. RESULTS: After residency, the female graduates' marital status differed from men's--more had never married or were divorced. Women's professional activities diverged from men's; their practice pattern was different, they spent more hours teaching, and they had fewer publications in peer-reviewed journals. This divergence was not accounted for by differences in pretraining interests or in training focus during residency. The authors present possible explanations. CONCLUSIONS: Further research is indicated to determine the underlying causes of career differences between women and men in psychiatric practice and academia so that effective strategies for correcting the present inequality of women in senior faculty positions can be implemented.

Four-year evaluation of a psychiatric clerkship: 1982-1986.

The authors describe a psychiatric clerkship organized to achieve goals relevant to all medical students, regardless of their future specialty choice. The clerkship had been in place for 8 years in 1986, and standardized program evaluations were available for 4 years. A survey of the diverse clinical settings used for the clerkship showed that each had unique strengths and weaknesses but that each could meet the core goals of the clerkship, indicating that this clerkship design would also be feasible in a smaller department with any one or two of the settings available.

Topsy--living and dying: a footnote to history.

This paper explores the significance of Marie Bonaparte's book, Topsy: The Story of a Golden Haired Chow. The manifest importance of Topsy has been attached to the fact that the Freuds translated it out of gratitude to Bonaparte and because of their love for dogs. Another level of significance emerges when the book is placed in historical context. Topsy elucidates the relationships between Marie Bonaparte, Sigmund Freud, and Anna Freud. It reflects Bonaparte's feelings about Freud's illness and is part of an ongoing dialogue with him. The persistent misplaced emphasis on the "dog story" has obscured the more profound issues. The author suggests that the conflicting needs to appreciate transience and to avoid mourning may account for both the importance of the book and for its obscurity.

Anorexia nervosa masking the diagnosis of spinal meningioma: a case report.

A case report of an adolescent female with signs and symptoms of both anorexia nervosa and high thoracic spinal cord meningioma is presented. Similarities in the presentation of both conditions are discussed, with emphasis on the early diagnosis of anorexia nervosa masking and delaying diagnosis of the thoracic meningioma. The contribution of the family and doctor-patient relationship in delaying the diagnosis are discussed. Pertinent literature is also reviewed.