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Advantages of working with organisms other than the model systems

Subash Lakhotia

Each of us has a favorite model organism to carry on research in the chosen field, to which we usually got addicted early in our careers. This addiction finds its origin and continuing support in the fact that the astounding developments in biological sciences during the past several decades have indeed largely been due to the concerted and concentrated efforts to understand life processes using a few model organisms. Each new development makes the model system more attractive and exciting. Consequently, the model organisms that were historically developed for a specific domain of study are now used for much wider spectrum of studies and with greater success. Comparison of the information gleaned from studies using the different model systems is providing a better understanding of living systems’ networks and their evolution, making the so-called “Systems Biology” increasingly more attractive.

Notwithstanding the great strides facilitated by the different model systems, their advantages can, in some respects, also limit our understanding of the diverse life forms. The diversity of organization, habitats and life styles of living organisms on this planet is enormous and as yet largely unfathomed. Compared to that, the multitude of model organisms commonly used across the globe present only a negligible diversity. This limitation of the model organisms is further compounded by the fact that most of these organisms in the laboratory are maintained under “5-star” luxury, which is far from the vagaries that their fellow beings have to face in nature.

The model organisms are essential for progress in Biology but should “modern biologists” remain confined to those few model systems only? Can we understand and appreciate the unbelievable diversity displayed by members of even one taxonomic group through our in-depth analyses of a few model organisms? In my mind, the obvious answer would be ‘No’. Yet, we often think that we can understand “life” through our increasingly precise and detailed understanding of the various molecular biological processes and their physiological network consequences using the model systems currently in vogue. Such a belief indeed reflects ignorance of the biological diversity. This ignorance or the unaware state of mind primarily stems from the fact that basic biology and natural history is hardly taught or learnt today (see one of my earlier blogs “Are we teaching Biology well?”). If one is not primed to appreciate the structural and functional diversity of living things, it is indeed difficult to appreciate the fact that the model systems reflect an extremely minor component of the biota.

Till about 2 decades ago, the zebra fish was hardly known in developmental biology or other fields of “modern biology”. Its introduction as a model system added a new dimension. Like the zebra fish or the puffer fish, there are numerous other organisms that can be used with great advantage for studying different life processes, from gross morphology to genomic organization on one hand and unusual life style to innovative physiological adaptations on the other. Recently, I had an occasion to read about the unusual life history of the “marbled crayfish” and was indeed impressed with its strange biology that has implications for basic reproductive strategies to epigenetics on one hand and stem cells to senescence on the other, to name a few. Like this animal, there are numerous others who are willing to offer themselves for enormously diverse and often, unanticipated, questions. The Indian sub-continent is very rich in bio-diversity and, therefore, offers unlimited scope for pioneering and immensely important research contributions. With significant public domain databases on genomics, rnomics, proteomics and other “omics”, undertaking in depth studies on gene expression, genomic organization, epigenetic processes etc are feasible today even in relatively unknown organisms as well. In many cases, classical cytological information for many of these organisms may also be available in the forgotten “pre-pdf era” literature. Using these organisms, equally or more important contributions are possible in the less fashionable “non-molecular biology” disciplines. All that is primarily required is a good question. Approaches, methods and information generated through studies on model systems can be effectively applied to the less known but more intriguing life systems.

While the young investigators need to take the first step out in the field, the peers and grant-approvers also need to change the philosophy that research programs should have some degree of guaranteed predictability. Research without any “risk” is not research at all. The confidence in success of work plan is good for publications where one wants to provide definitive mechanistic explanations (in great demand by the high IF journals!) but that does not necessarily guarantee pioneering research. On the other hand, pioneering work, with little “hi-fi” laboratory facilities, on an unusual life style organisms may often be able to excite even the very high IF journal editor with little “mechanistic details”!