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Tradeoffs and Social Behaviour in the Cellular Slime Moulds S Tradeoffs and social behaviour in the cellular slime moulds S. Sathe To cite this version: S. Sathe. Tradeoffs and social behaviour in the cellular slime moulds. Life Sciences [q-bio]. Indian Institute of Science, 2012. English. tel-01052814 HAL Id: tel-01052814 https://tel.archives-ouvertes.fr/tel-01052814 Submitted on 28 Jul 2014 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Trade­offs and social behaviour in the cellular slime moulds A Thesis submitted for the degree of Doctor of Philosophy in the Faculty of Science by Santosh Sathe Centre for Ecological Sciences Indian Institute of Science Bangalore‐ 560012 INDIA October 2011 DECLARATION I hereby declare that the work reported in this thesis titled, “Trade‐offs and social behaviour in the cellular slime moulds” is the result of investigations carried out by me at the Centre for Ecological Sciences (CES), Indian Institute of Science, Bangalore, under the supervision of Prof. Vidyanand Nanjundiah. I further declare that this work has not formed the basis for an award of any degree, diploma or fellowship in any institution. October 2011 Santosh Sathe Dedicated to Tai and Nana..... Acknowledgments I would like to express my genuine gratefulness to my thesis advisor Prof. Vidyanand Nanjundiah for his support and encouragement throughout this work. His expertise and understanding of the subject was extremely useful while solving many issues mentioned in this thesis. His help in writing reports, conference abstracts, research publications and this thesis is duly acknowledged. I acknowledge the senior research fellowship (SRF) from Council of Scientific and Industrial Research and the financial assistance from Indian Institute of Science, India. I would also like to thank “German Genetics society” and the “Japan Society for the Promotion of Science in Japan” for financial support during my stay in Germany and Japan for attending conferences on Dictyostelium. Very special thanks go out to Dr. Aggarwal and his research group for their help and allowing me to work at the Centre for Cellular and Molecular Biology (Hyderabad). Many thanks to Neha for her assistance in performing some of the experiments mentioned in chapter 4 of this thesis. Many helpful suggestions from Prof. R. Borges, Prof. J. T. Bonner, Prof. C. Nizak, Prof. N. Joshi, Anusha and Mahua helped to improve the quality of this thesis. Uveraj, Brijesh and Lakshya thank you for helping me during my colloquium. Prof. Mahadevan, a very lively person, was a constant source of encouragement and always ready to spend time with me; discussions with him on scientific as well as non‐scientific issues were very useful. I would like to thank my teachers from the Ahmednagar College and the University of Pune (especially Dr. Deopurkar). I was fortunate to have intelligent seniors in the laboratory (Ritwick, Nameeta, Stuti, Sanki, Ranjna, Aashiq, and Smita); I would like to thank all of them for their help and guidance. My stay at IISc was joyful and this is because of the social environment created by many of my good friends. It will not be possible to mention all the names; here are a just few of them: Vinod, Navanath, Prasad, Ravi, Pooja, Ritesh, Sharad, Manoj, Savita, Jassi, Dubey, Kaka, Alok, Manjari, Ratna, Smita and Soumya. I would like to thank all the faculties from CES and MRDG. I also extend my thanks to the department staff that have helped in numerous ways: Basavraj, Bharathi, Selveraj, Raghvendra, Lakshmi, and Anathu. I am very thankful to all the members of DBGL. Special thanks to the IISc hockey club, C and B mess members and several friends over there. The names mentioned here are very special people in my life; their presence meant a lot to me. Thank you very very very much Sandip, Mahua, Hari, Neeraja and Femi. Finally, I would like to thank my family for the support they have provided to me throughout my entire life; without their love and encouragement I would not have come this far. I sincerely apologize to all whose names have been missed inadvertently. The defects remaining in this thesis are unintentional and my responsibility alone. Publications 1. Sathe, S., et al., 2010. Genetic heterogeneity in wild isolates of cellular slime mold social groups. Microb Ecol. 60, 137-48. 2. Sathe, S., Khetan, N. and Nanjundiah, V., 2014. Interspecies and intraspecies interactions in social amoebae. Journal of Evolutionary Biology. 27: 349–362. 3. Nanjundiah, V., Sathe, S., 2011. Social selection and the evolution of cooperative groups: The example of the cellular slime moulds. Integr. Biol. 3, 329-342. 4. Nanjundiah, V., Sathe, S., 2013. Social selection in the cellular slime moulds. In: Dictyostelids: Evolution, Genomics and Cell Biology (M. Romeralo, S. Baldauf & R. Escalante, eds). Springer-Verlag, Berlin, Heidelberg, pp. 193–217. 5. Sathe, S., et al., 2011. Development of twelve polymorphic microsatellite markers from the social amoeba Dictyostelium giganteum suitable for genetic diversity studies on cellular slime moulds (Permanent Genetic Resources added to Molecular Ecology Resources Database 1 August 2010 – 30 September 2010). Molecular Ecology Resources. 11, 219-222. 6. Sathe, S., Nanjundiah, V., Trade-offs as a basis for cooperation in a social amoeba (in preparation). Index TABLE OF CONTENTS Synopsis…………………………………………………………………………………………………………………...1 Chapter 1: Cooperative behaviour in the social amoebae. 1.1 Introduction…………………………………………………………………………………………………………6 1.2 Glossary……………………………………………………………………………………………………………….7 1.3 Examples of cooperative behaviour………………………………………………………………………8 1.4 Evolutionary explanations for cooperation……………………………………………………………9 1.5 Cellular slime moulds…………………………………………………………………………………………13 1.6 Survival strategies……………………………………………………………………………………………...15 1.7 ‘Altruistic’ behaviour in CSMs……………………………………………………………………………..21 1.8 References…………………………………………………………………………………………………………30 Chapter 2: Large mammals as dispersal agents and genetic heterogeneity in wild isolates. 2.1 Introduction……………………………………………………………………………………………………….40 2.2 Cellular slime moulds in nature…………………………………………………………………………..41 2.3 Cellular slime moulds from India………………………………………………………………………...42 2.4 Dispersal vectors………………………………………………………………………………………………..43 2.5 Diversity in the wild and genetic heterogeneity within social groups……………………45 2.6 Materials and methods……………………………………………………………………………………….50 2.6.1 Sample collection………………………………………………………………………………….50 2.6.2 Isolation of CSMs from animal dung and soil………………………………………….53 2.6.3 Estimating genetic heterogeneity within fruiting bodies…………………………54 2.6.4 DNA isolation………………………………………………………………………………………..55 2.6.5 Random Amplification of Polymorphic DNA…………………………………………...55 2.6.6 Isolation of bacteria………………………………………………………………………………56 2.6.7 Identification of bacterial isolates………………………………………………………….57 2.6.8 Statistical analysis................................................................................................................57 2.7 Results……………………………………………………………………………………………………………….59 Index 2.7.1 Presence of CSM in large mammal dung…………………………………………………59 2.7.2 CSMs from soil………………………………………………………………………………………63 2.7.3 Genetic heterogeneity in CSM social groups……………………………………………70 2.7.4 Bacteria from Mudumalai forest soil………………………………………………………73 2.8 Discussion………………………………………………………………………………………………………….74 2.8.1 Large mammals as CSM dispersal agents………………………………………………..74 2.8.2 Genetic diversity in fruiting bodies………………………………………………………...76 2.9 References………………………………………………………………………………………………………....81 Chapter 3: Trade­offs as a basis for cooperation and coexistence in Dictyostelium giganteum. 3.1 Introduction……………………………………………………………………………………………………….86 3.2 Materials and methods…………………………………………………………………………………….....88 3.2.1 D. giganteum strains.……………………………………………………………………………..88 3.2.2 Growth.………………………………………………………………………………………………...89 3.2.3 Developmental rate.………………………………………………………………………………91 3.2.4 Slug migration through soil.…………………………………………………………………..92 3.2.5 Sporulation efficiency in mixtures.…………………………………………………………93 3.3 Results.………………………………………………………………………………………………………………95 3.3.1 Growth.………………………………………………………………………………………………...95 3.3.2 Post‐starvation developmental rate.………………………………………………………96 3.3.3 Slug migration through soil.…………………………………………………………………..99 3.3.4 Sporulation efficiency.…………………………………………………………………………103 3.4 Discussion.……………………………………………………………………………………………………….110 3.4.1 Caveats.………………………………………………………………………………………………110 3.4.2 Trade‐offs.…………………………………………………………………………………………..113 3.4.3 How does this study help us to understand cooperation in Dictyostelium giganteum?...........................................................................................................................115 3.5 References………………………………………………………………………………………………............119 Index Chapter 4: Chimaerism and segregation in inter­species mixtures of Dictyostelium purpureum and D. giganteum. 4.1 Introduction…………………………………………………………………………………………………….123 4.2 Inter‐species interactions…………………………………………………………………………………123 4.3 Materials and
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