Day Date Subject To be read prior to this class period: T 1/13 Setting the stage Th 1/15 Capstone course planning T 1/20 Life Span Cynthia Kenyon’s Lab handouts Th 1/22 Capstone Topics. Life span discussion T 1/27 Chapter 1 Th 1/29 Chapter 3 T 2/3 students = gut bacteria and development Jennifer Ditano, Afaq Lamlum Th 2/5 Chapter 2 T 2/10 students = hormonal control of sex determination Raisa Luck, Susan Duong Th 2/12 Chapter 5 T 2/17 no class - Winter Break Th 2/19 no class - Winter Break T 2/24 Th 2/26 Chapter 6 T 3/3 students = endocrine disruptors Meg Thurell, Nicole Bordeau Th 3/5 T 3/10 Midterm Exam 1 From the Preface of our textbook: “Development weaves genotype and environment into phenotype.” From the Preface of our textbook: “Development weaves genotype and environment into phenotype.” 4 identical twins schizophrenia discordance = when identical twins have different phenotypes 5 polyphenism = two or more discrete phenotypes from one genotype 6 Evidence the following contributes to aging and life span: 1) gene regulation using a polyphenism as a model example 2) normal metabolism “higher metabolism = shorter life span” free radicals repair mechanisms mitochondria caloric restriction 3) low level stress induction caloric restriction 4) telomere shortening 7 Why are we studying aging as a topic in this course? 1) Life span is based on the rate of aging and although aging has seemed like a physiological ‘wear and tear’, it now seems to be related to growth / reproduction and those are developmental processes. 2) Life span is inherited (there is a program represented in the genetic code – genotype). 3) The life span phenotype is not always constant, but can affected by the environment (phenotypic plasticity). 4) The study of model examples of phenotypic plasticity is helping us understand complex but fundamental principles 8 of development. POSSIBLE EXAM QUESTION Why are we studying aging as a topic in this course? 1) Life span is based on the rate of aging and although aging has seemed like a physiological ‘wear and tear’, it now seems to be related to growth / reproduction and those are developmental processes. 2) Life span is inherited (there is a program represented in the genetic code – genotype). 3) The life span phenotype is not always constant, but can affected by the environment (phenotypic plasticity). 4) The study of model examples of phenotypic plasticity is helping us understand complex but fundamental principles 10 of development. 11 12 13 14 Figure 1.15 Predator-induced and typical morphs of genetically identical individuals of Daphnia transgenerational Reduced numbers of eggs. Chapter 3: Co-Development During Symbioses 16 17 18 19 POLYPHENISM (?) 20 21 squid with bacteria squid without bacteria 22 23 24 25 metazoan / microbe symbioses How are microbes acquired/transmitted? 1) acquired from the environment 2) horizontal transmission 3) vertical transmission How are microbes maintained? How is host development affected? 26 Chapter 3: Symbioses parasitism mutualism commensalism Some of Gilbert’s examples are about environmental modulation of development and some aren’t. 27 Life Cycle Symbioses pollination 28 Plant / fungus symbioses: Endophytes Mycorrhizae 29 Wolbachia Bacteria transmitted primarily by being in the cytoplasm of the egg. Therefore, natural selection favor increasing the proportion of females: 1)male lethality = less competition for resources 2)males change sex 3)“male” parthenogenesis 4)cytoplasmic incompatibility 30 Organisms often form symbioses not just with one microbial species but with several = microbial consortia. An oligochaete worm, Olavius algarvensis No mouth, anus, or gut. Hosts a sulfur-metabolizing bacterium and three other species. 31 Mammalian gut development introduction to gut environment and biofilms 1) bacteria and blood capillary development 2) GALT = Gut Associated Lymphoid Tissue 3) gut bacteria and obesity (probiotics) 32 Mammalian gut development 1) bacteria and blood capillary development 2) GALT = Gut Associated Lymphoid Tissue 3) gut bacteria and obesity (probiotics) 33 34 35 36 Mammalian gut development 1) bacteria and blood capillary development 2) GALT = Gut Associated Lymphoid Tissue 3) gut bacteria and obesity (probiotics) 37