Dissertations and Theses @ UNI

Availability

Open Access Thesis

Keywords

Genes--Identification; Ascospores; Aspergillus; Genes; Field guides;

Abstract

This study is one of the first molecular characterizations of a gene whose expression is exclusive to ascospores of Aspergillus nidulans. A 900 base pair (bp) fragment of this gene was cloned into a modified pUC19 plasmid and used to transform uridine auxotrophs of A. nidulans. Previous studies showed that A. nidulans is amenable to DNA mediated transformation by site-specific recombination (Fincham , 1989). Transformants were severely deficient in the production of ascospores, with decreases in viable ascospores per cleistothecia of 80-99.75%. Southern blotting experiments confirmed that integrative homologous transformation occurred in all cases, and that a tandem insertion is likely in the most severely defective transformant. The observed decrease in the production of viable ascospores was also correlated to a lack of the 77 kD protein product of the asp77 gene in the transformants. Approximately 90% of the 900 bp fragment was sequenced, but despite the presence of a number of consensus sequences, a consistent reading frame was not discovered. PCR experiments showed that the gene was present in one copy on the genome of Aspergillus nidulans. The discovery of a gene whose expression product is specific to ascospores provides an opportunity to use the asp 77 product to: 1) mark for the onset of sexual differentiation, and 2) investigate the genetic regulation of ascosporogenesis.

Year of Submission

1998

Degree Name

Master of Arts

Department

Department of Biology

First Advisor

James E. Jurgenson

Second Advisor

Darrell Wiens

Third Advisor

Alan Orr

Comments

If you are the rightful copyright holder of this thesis and wish to have it removed from the Open Access Collection, please submit a request to scholarworks@uni.edu and include clear identification of the work, preferably with URL.

Date Original

1998

Object Description

1 PDF file (95 leaves)

Language

en

File Format

application/pdf

Included in

Biology Commons

Share

COinS