Copyright © 2009 Pearson Education, Inc. PowerPoint ® Lecture Presentation for Concepts of Genetics Ninth Edition Klug, Cummings, Spencer, Palladino Chapter 9 Extranuclear Inheritance Lectures by David Kass with contributions from John C. Osterman. Copyright © 2009 Pearson Education, Inc.
Examples of Extranuclear Inheritance Organelle heredity Infectious heredity Maternal effect
Copyright © 2009 Pearson Education, Inc. Chloroplast DNA (cpDNA) Ranges from 100 to 225 kb in length, and the genes carried on the DNA encode products involved in photosynthesis and translation. Circular, double- stranded DNA Section 9.2
Copyright © 2009 Pearson Education, Inc. Chloroplast
Copyright © 2009 Pearson Education, Inc. Mitochondrial DNA (mtDNA) Circular, double-stranded DNA is smaller than the DNA in chloroplasts, and introns are absent. Most of the protein encoding genes are located on a single strand. The contribution of nuclear and mitochondrial gene products is shown in Figure 9.8. Section 9.2
Copyright © 2009 Pearson Education, Inc. Mitochondrion
Copyright © 2009 Pearson Education, Inc. Figure 9.8
Copyright © 2009 Pearson Education, Inc. Endosymbiotic Theory
Copyright © 2009 Pearson Education, Inc. Inheritance of chloroplast or mitochondrial traits is often determined by the phenotype of the ovule source (Figure 9.1). Section 9.1
Copyright © 2009 Pearson Education, Inc. Figure 9.1 Four O’Clock Plants
Copyright © 2009 Pearson Education, Inc. Chlamydomonas is an excellent model system for studying organelle heredity because it has a single large chloroplast that exhibits a uniparental inheritance pattern. Section 9.1
Copyright © 2009 Pearson Education, Inc. Mitochondrion Heteroplasmy
Copyright © 2009 Pearson Education, Inc. For a human disorder to be attributed to mitochondrial DNA: the inheritance must exhibit a maternal inheritance pattern the disorder must reflect a deficiency in the bioenergetic function of the organelle there must be a specific mutation in a mitochondrial gene Section 9.3
Copyright © 2009 Pearson Education, Inc. Three disorders arising from mtDNA are: myoclonic epilepsy and ragged red fiber disease (MERRF) Leber’s hereditary optic neuropathy (LHON) Kearns–Sayre syndrome (KSS) Section 9.3
Copyright © 2009 Pearson Education, Inc. MERRF Normal Skeletal Muscle. Cross- section jpg MERRF Cells
Copyright © 2009 Pearson Education, Inc. 9.5In Maternal Effect, the Maternal Genotype Has a Strong Influence during Early Development
Copyright © 2009 Pearson Education, Inc. Figure 9.12
Copyright © 2009 Pearson Education, Inc. Figure 9.13
Copyright © 2009 Pearson Education, Inc. The End