Profiling expression changes caused by a segmental aneuploid in maize

<p>Abstract</p> <p>Background</p> <p>While changes in chromosome number that result in aneuploidy are associated with phenotypic consequences such as Down syndrome and cancer, the molecular causes of specific phenotypes and genome-wide expression changes that occur in aneuploids are still being elucidated.</p> <p>Results</p> <p>We employed a segmental aneuploid condition in maize to study phenotypic and gene expression changes associated with aneuploidy. Maize plants that are trisomic for 90% of the short arm of chromosome 5 and monosomic for a small distal portion of the short arm of chromosome 6 exhibited a phenotypic syndrome that includes reduced stature, tassel morphology changes and the presence of knots on the leaves. The knotted-like homeobox gene <it>knox10</it>, which is located on the short arm of chromosome 5, was shown to be ectopically expressed in developing leaves of the aneuploid plants. Expression profiling revealed that ~40% of the expressed genes in the trisomic region exhibited the expected 1.5 fold increased transcript levels while the remaining 60% of genes did not show altered expression even with increased gene dosage.</p> <p>Conclusion</p> <p>We found that the majority of genes with altered expression levels were located within the chromosomal regions affected by the segmental aneuploidy and exhibits dosage-dependent expression changes. A small number of genes exhibit higher levels of expression change not predicted by the dosage, or display altered expression even though they are not located in the aneuploid regions.</p

Brd1 Gene in Maize Encodes a Brassinosteroid C-6 Oxidase

The role of brassinosteroids in plant growth and development has been well-characterized in a number of plant species. However, very little is known about the role of brassinosteroids in maize. Map-based cloning of a severe dwarf mutant in maize revealed a nonsense mutation in an ortholog of a brassinosteroid C-6 oxidase, termed brd1, the gene encoding the enzyme that catalyzes the final steps of brassinosteroid synthesis. Homozygous brd1–m1 maize plants have essentially no internode elongation and exhibit no etiolation response when germinated in the dark. These phenotypes could be rescued by exogenous application of brassinolide, confirming the molecular defect in the maize brd1-m1 mutant. The brd1-m1 mutant plants also display alterations in leaf and floral morphology. The meristem is not altered in size but there is evidence for differences in the cellular structure of several tissues. The isolation of a maize mutant defective in brassinosteroid synthesis will provide opportunities for the analysis of the role of brassinosteroids in this important crop system

INTD3990-IM.Internship*.F13.Makarevitch,Irina

An internship is a student planned and faculty supervised experience integrating work and study. Internships allow students to integrate their academic, professional, and personal development. Students are expected to develop goals in each of these areas and to complete reflective and academic work in conjunction with work completed at the internship site. There are incredible opportunities available in the Twin Cities and throughout the United States. For more information, stop by the Career Development Center, Drew Science 113. The CDC staff can assist you with finding and registering an internship. Phone: 651-523-2302; e-mail: [email protected]. Available to College of Liberal Arts students only

BIOL3870-B1.LAB: Genomics & Bioinformatics.J16.Makarevitch,Irina

Goals: This course was developed to familiarize students majoring in biology with the methods of genomic research, to encourage students to think on genomic scale, to help students become proficient with computer tools to do genomics, to promote student understanding the relationships between science and newspaper headlines. Content: This course examines major ideas of the current genomics research. It also introduces students to biology resources available online. Through the series of exercises and case studies, students will practice conducting DNA and protein sequence analysis, primary literature analysis, interpreting results of gene expression studies and more. We will talk about ethical and scientific aspects of genomic research including human genome project and DNA testing. Taught: Winter Prerequisites: BIOL 3050 Credits:

INTD3990-IM0.Internship*.Su15.Makarevitch,Irina

An internship is a student planned and faculty supervised experience integrating work and study. Internships allow students to integrate their academic, professional, and personal development. Students are expected to develop goals in each of these areas and to complete reflective and academic work in conjunction with work completed at the internship site. There are incredible opportunities available in the Twin Cities and throughout the United States. For more information, stop by the Career Development Center, Drew Science 113. The CDC staff can assist you with finding and registering an internship. Phone: 651-523-2302; e-mail: [email protected]. Available to College of Liberal Arts students only

BIOL5600-BA.Developmental Biology.Sp16.Makarevitch,Irina

Goals: To survey developmental processes in a variety of protists, plants and animals. To design and perform experiments that address topics chosen by students, using developmental systems. To practice writing skills. Content: The genetic basis of development, sexual reproduction, morphogenesis and embryonic development in animals, plant development, pattern formation, regeneration, metamorphosis, and aspects of cancer and aging. Taught: Alternate years, spring term Prerequisite: BIOL 3050 and 3060 NOTE: Students must concurrently register for a lecture and a corresponding 0-credit lab section of this course. Credits:

BIOL1180-BA.Biotechnology in Your Life.Su15.Makarevitch,Irina

Goals: Engage non-science majors in thinking about biotechnology, its controversies and promises. To develop skills in critical thinking and analysis by testing claims of superior qualities of various biotechnology products. Content: This course examines major products of biotechnology and their effects on our life today. We will talk about ethical and scientific aspects of genetically modified food, human cloning, recombinant drugs and much more... We will look into news, talk about your groceries, and think about new approaches to regulate new technologies. We will also try to understand how all that biotech works! Taught: Summer Credits: 4 credit

BIOL3050-D2.LAB: Principles of Genetics.F15.Makarevitch,Irina

Goals: To acquire an understanding of the basic principles of transmission genetics, molecular genetics and population genetics. Students will be able to explain these principles and discuss projects and problems in which these principles are relevant. To gain experience in the practice of science by posing scientific questions, designing experiments or observations to answer these questions and presenting the results of these studies in a public forum. To increase skills in the following areas: Oral and written communication, use of the computer as a scientific tool, functioning as a member of a goal directed team. Content: Mendelian genetics, genetic mapping, cytogenetics and chromosome abnormalities, genetic engineering methods and applications, genomics, gene regulation and developmental genetics, the genetics of cancer, population genetics and microevolution. Taught: Fall term Prerequisites: CHEM 1130 or CHEM 1500 (grade of C- or better) or concurrent registration; BIOL 1820 (grade of C- or better), or consent of the instructor NOTE: Students must concurrently register for a lecture and a corresponding 0-credit lab section of this course. Credits: