Syllabus del corso
Obiettivi
Tutti gli organismi viventi interagiscono con altri organismi nel corso della loro intera esistenza. Nei casi estremi, come le simbiosi intracellulari, l’habitat di un organismo è addirittura un altro vivente. Lo studio di queste interazioni avviene integrando diverse fonti di informazione biologica (zoologia, genetica, fisiologia, ecologia, microbiologia, bioinformatica, ecc.). Comprendere le caratteristiche e i fini meccanismi coinvolti in queste interazioni è una grande sfida della scienza di base e ha numerosi risvolti applicativi che spaziano dalla conservazione della biodiversità e degli ecosistemi alla caratterizzazione delle comunità microbiche che influenzano la salute umana o che permettono le principali attività di biotrasformazione delle risorse naturali. 1) Conoscenza e Capacità di Comprensione: Al termine dell'insegnamento lo studente acquisirà conoscenze riguardo i diversi livelli di complessità delle interazioni nel contesto animale, da quelle con organismi simbionti unicellulari, a quelle con l'ambiente (es. servizi ecosistemici). Inoltre verranno affrontate tematiche relative alla manipolazione comportamentale di ospiti animali a seguito di interazioni con altri organismi. 2) Capacità di applicare conoscenza e comprensione:
Al termine dell'insegnamento lo studente dovrà essere in grado di applicare le conoscenze acquisite al punto 1 a materie o percorsi di tesi che affronterà in futuro. 3) Autonomia di giudizio: Lo studente dovrà essere in grado di elaborare in modo critico quanto appreso e scegliere l’approccio più adeguato per collegare le caratteristiche funzionali di organisimi animali a livelli di interazione complessi estesi quali ad esempio i servizi ecosistemici. 4) Abilità comunicative: Alla fine dell'insegnamento lo studente saprà descrivere in modo chiaro e con proprietà di linguaggio le diverse tipologie di interazioni animali e i loro effetti sia in ambito evoluzionistico che applicativo (ad es. bioprospecting, servizi ecosistemici). 5) Capacità di apprendimento: Alla fine dell'insegnamento lo studente avrà le competenze necessarie per affrontare in autonomia gli studi successivi che richiedano conoscenze di simbiosi, identificazione molecolare di organisimi e loro interazioni. Inoltre lo studente sarà in grado di associare e integrare le conoscenze apprese con i concetti che assimilerà negli insegnamenti futuri.
Contenuti sintetici
L'insegnamento si occupa di affrontare in modo integrato e a più livelli lo studio delle interazioni biologiche in cui sono coinvolti organismi animali. Ci sono molte modalità con cui questo insegnamento potrebbe essere trattato. Nell'insegnamento erogato presso il nostro corso di studi verrà offerta una panoramica dei principali tipi di interazione e delle basi evolutive e funzionali ad essi connesse. Particolare attenzione sarà rivolta alle applicazioni in ambito conservazionistico, gestionale e di bioprospecting delle tipologie di interazione trattate.
Programma esteso
General aspects of animals’ interactions
• Definition and importance of biological interactions
• Functional diversity and interaction diversity
o Interaction networks
• Why study animals’ biological interactions?
o Theoretical aspects (metanalyses)
o Ecosystem services
o Conservation biology issues (extinction of species vs. extinction of interactions)
o Human health (bioprospecting)
o Social and economic issues
• The diversity of animals’ interactions
o The multilevel characterization of animal interactions
A focus on symbioses
• Definitions (symbiosis, host, symbiont)
• Historical aspects
• Classification of interactions
o Antagonistic interactions
o Mutualistic interactions
o Consumption interactions
o Competitive interaction (amensalism, allelopathy, antibiosis)
• Framing the interactions (exploitation competition, apparent competition)
• Types of symbiosis (and examples)
o Commensalism
o Amensalism
o Inquilinism
o Phoresy
o Parasitism and parasitoids
• Indirect effects of mutualism
• The problem of classifying symbiotic interactions
• Sexual parasitism
• How context-dependent are species interactions?
The challenge of identification
• Why do we need to identify the “interactors”?
• Limitations of classical identification approaches
• Is species identification challenging?
• Molecular identification (target and untarget DNA-based approaches)
o DNA barcoding
Integrative taxonomic concepts (MOTUs, IOTUs, UCSs, DCLs, CCSs)
o DNA metabarcoding
Environmental DNA
DNA metabarcoding to identify animal interactions
Modern applications of eDNA
o Metagenomics
o Metatranscriptomics
Intracellular symbioses
• Definitions and context
• The domains of life (Archaea, Bacteria, Eucarya)
• The endosymbiotic origin of eukaryotes
o Endosymbiosis (historical aspects)
o The Serial Endosymbiosis Theory (SET)
Which supports to the SET (case studies and other biological aspects)
Undulipodia
Set chronology
o The origin of mitochondria
Mitochondrial early theory
Mitochondrial late theory
Syntrophic hypothesis
o The origin of plastids
o The origin of other organelles (peroxisomes)
o The origin of the nucleus
Chimeric origin
Viral origin
• The original host (new theories)
Insects – bacteria interactions
• General aspects
o Primary and secondary symbionts
Bacteriocytes, co-phylogeny, genome shrinkage
Vertical vs. horizontal transmission
• Why insects need intracellular symbiotic bacteria?
• Case study: Aphids and Buchnera
• Case study: pseudococcidae and bacteria
• Other case studies on sap-feeding insects: Bemisia tabaci
• Stolen genes & nutritional interactions
o The Horizontal Gene Transfer
o Case studies
• Other intracellular symbioses in insects
o Camponotus ants and Blochmannia
o Cockroaches and Blattabacterium
• Hematophagous insects
o Case study: Glossina flies and Wigglesworthia / Sodalis
Other intracellular nutritional interactions
• Case study: Olavius algarvensis
• Case study: Bathymodiolus molluscs
• Case study: Riftia pachyptila
• Case study: Osedax mucofloris
Sacoglossa and kleptoplasty interactions
Wolbachia
• Historical aspects
• Effects and transmission of Wolbachia in filarioid nematodes and arthropods
• Origin, occurrence and diversification of Wolbachia
o Wolbachia supergroups
Phylogenetic assessment of supergroups and problems
The enigma of supergroup F
• The manipulation of genetic diversity and sex-ratio in insects mediated by Wolbachia
o Cytoplasmatic incompatibility
Unidirectional vs. bidirectional
Wolbachia infection and species delimitation in insects
Case study: Ischnura spp.
Case study: Andrena spp.
o Induced parthenogenesis
o Male-killing effect
o Genetic males feminization
o Multi-potent effects
o Positive effects
o True Parasitism
• Wolbachia: Lateral gene transfer to eukaryotes hosts
• Aside Wolbachia: the Torix bacteria
Bioluminescence interactions
• Definition and base concepts
• The mechanisms of bioluminescence
o Horizontal Gene Transfer
o Diet
o Symbiosis
• Case study: Euprymna scolopes and Vibrio fischeri
o Vibrio fischeri colonization mechanism and timing
o Modification in E. scolopes induced by V. fischeri
o Modification of V. fischeri after the colonization
o Regulation mechanisms of the interaction
o The induction of bioluminescence
• Other bioluminescent symbiotic bacteria
Pollination
• Pollination ecology: single species and complex networks
• investigating the impact of anthropogenic stressors on pollinator insects
• Connections between pollinators health and human health: a nutritional perspective
Seed dispersal
• Background and importance
• The plant “point of view”
o Seed Dispersal Effectiveness
o Seed Rain
o Study cases
• The disperser “point of view”
• Seed dispersal and migration
o The frugivory paradox
o The geographic scale of seed dispersal
Short-ranged dispersal
Long distance dispersal
• How to study seed dispersal
o Case studies
• Global drivers of seed dispersal
o Defaunation
o Invasive species
• Seed dispersal and restoration
Host manipulation by parasites
• Background and relevance in the context of animal interactions
o The “hitch-hiking” hypothesis
o Positive effects of manipulation on the host
• Historical aspects
• Evolutionary aspects
o Manipulation sensu stricto
o Facultative virulence: mafia-like strategy
o Exploitation of compensatory responses
o The evolution of manipulation after its emergence
• Adaptative significance of host manipulation
• Mechanisms behind host’s behavior manipulation
o Case study: Toxoplasma gondii
o Case study: Neuroviruses
o Case study: Gammarids and Acanthocephalans
o Case study: Suicidal crickets
o Case study: Bodyguard manipulation
o Case studies: Fungi and “Zombie” insects
o Case Study: the extreme autotomy in Sacoglossan molluscs
o A possible role of host/parasite microbiomes?
• Manipulation of plant phenotype
o Background and relevance
o Manipulation mediated by herbivores
Shelter-building herbivores
Canal cutting insects
Green islands-inducing insects
o Manipulation of plant-pollinator interactions
• Visual trickery in avian brood parasites
o Case study: Cuculus canorus
o Case study: the widow birds
• Brood care host manipulation
• Social host manipulation
SEMINARS:
Prerequisiti
Microbiologia, Zoologia, Conoscenze di base di biologia cellulare e molecolare.
Modalità didattica
Lezioni frontali. Alcune lezioni potrebbero essere effettuate in modalità di seminario specialistico tenuto da ricercatori esperti nei settori trattati durante il corso.
Materiale didattico
Articoli scientifici comunicati dal docente durante le lezioni. Gli studenti potranno ottenerli avvalendosi delle risorse bibliotecarie di ateneo a cui hanno accesso. Verranno rese disponibili su piattaforma elearning di ateneo le slides delle lezioni e dei seminari.
Periodo di erogazione dell'insegnamento
Primo semestre
Modalità di verifica del profitto e valutazione
L'accertamento delle conoscenze per l'insegnamento in oggetto consisterà in un esame finale orale. Non sono previste prove in itinere. L'esame inizierà con la discussione critica di un articolo scientifico, scelto dallo studente e approvato preventivamente dal docente riguardante le tematiche generali trattate nell'insegnamento. Avrà luogo quindi l'accertamento degli argomenti inclusi nel programma dell'insegnamento.
Orario di ricevimento
Su appuntamento previa email al docente (andrea.galimberti@unimib.it)
Sustainable Development Goals
Aims
All living beings interact with other organisms during their life’s cycle. In extreme cases such as intracellular symbioses, habitat could act as another organism. The study of these interactions is conducted by integrating different sources of biological information (zoology, genetics, physiology, ecology, microbiology, bioinformatics). Understanding characteristics and the mechanisms involved in such biological interactions is challenging in a context of base science. This kind of investigation also has many applicative outcomes ranging from biodiversity and ecosystems conservation to the characterization of microbial communities. Microbiomes influence human health and allows the principal activities of biotransformation of natural resources. 1) knowledge and understanding: A the end of the course, the student will have acquired knowledge regarding the different levels of complexity of interactions in the animal context, from those involving microbial organisms to those with the environment. Moreover, topics related to the host behavior manipulation mediated by interaction with other organisms will be discussed. 2) Applying knowledge and understanding: At the end of the course, the student will be able to apply the knowledge acquired during the course to other courses or thesis programs involving the issue of animal interactions. 3) Making judgements: The student will be able to critically adopt the acquired knowledge and choose the most reliable approach to link the functional traits of organisms to their possible complex interactions, for example in a context of ecosystem services. 4) Communication skills: At the end of the course, the student will be able to describe clearly, and with an adequate language the different types of interactions and their effects in terms of evolutionary aspects and applied contexts (e.g., bioprospecting). 5) Learning skills: At the end of the course, the student will have the necessary knowledge to deal with the next studies that will require knowledge of symbioses, molecular identification of organisms and their interactions. Finally, the student will be able to associate and integrate the acquired knowledge with the concepts belonging to the successive courses.
Contents
The course aims at discussing the study of biological interactions involving animal species under an integrative and multilevel approach. There are many possible ways to treat these topics. In this course, provided in the framework of our master program, it will be offered a wide overview concerning the principal kinds of interactions, including their evolutionary and functional aspects. Specific attention will be devoted to the application of animals' biological interactions in terms of conservation, management of natural resources and bioprospecting.
Detailed program
- Diversity of biological interactions and importance of their study at both the theoretical and applied level.
- The concept of “symbiosis” and description of the different typologies.
- The challenge of identification. Brief description of the principal analytical techniques used for studying the diversity and dynamics of animal’s biological interactions.
-The massive DNA sequencing revolution and its applications in the field of environmental and agroecosystems interactions (eDNA, DNA metabarcoding and metagenomics).
- Interactions between microorganisms as a model to explain the origin of Eukaryotes.
- Intracellular symbioses (case studies of medical, veterinary and phytosanitary importance and the applicative outcomes deriving from their characterization).
- Eukaryotes interactions in natural and agricultural systems (e.g., pollination, seed dispersal) and the problem of biological invasions.
- Manipulation of animals’ behaviour mediated by parasites (case studies and applications of human interest).
Prerequisites
Microbiology, Zoology, basic knowledge of cell biology and molecular biology.
Teaching form
Lectures in the classroom. Some lessons could be seminars hold by experts in the sectors discussed during the course.
Textbook and teaching resource
Scientific articles provided by the teacher during lessons. Students can obtain them by accessing to the electronic library of the University. The slides of classoroom lessons and seminars will be available on the elearning Platform.
Semester
First semester
Assessment method
The verification of the knowledge aquired during the course will consist in an oral examination at the end of the course. There will be not intermediate tests. The examination will start with the critique discussion of a scientific article chosen by the student (and previously approved by the teacher), concerning the general issues treated in the lessons. The examination will continue with the discussion of the arguments included in the program of the course.
Office hours
Upon request by email (andrea.galimberti@unimib.it)
Sustainable Development Goals
Staff
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Andrea Galimberti
