Marsupials Hold the Key to Understanding the Evolution of Heater Organs in Mammals
Around 100 million years ago, a significant evolutionary development allowed placental mammals to thrive and adapt to colder regions. Recent research conducted by Stockholm University reveals that the unique mammalian heater organ, brown fat, evolved specifically in modern placental mammals. This groundbreaking study, published in the prestigious journal Science, sheds light on the origins and significance of brown fat in mammalian evolution.
Collaborating with experts from Helmholtz Munich, the Natural History Museum Berlin, and the University of East Anglia, the research team from Stockholm University made a fascinating discovery regarding marsupials, our distant relatives. They found that marsupials possess a primitive form of brown fat that has not fully evolved compared to modern placental mammals. This crucial finding highlights the role of brown fat in mammalian evolution, endothermy, and metabolism.
Susanne Keipert, co-first author of the study, emphasized the importance of their research in understanding the origin and function of brown fat. Brown fat’s energy-consuming properties have garnered significant attention in medical research due to its potential in addressing obesity, diabetes, and other metabolic diseases that pose a threat to public health.
The study conducted by the Jastroch Laboratory at Stockholm University uncovered that marsupials exhibit active transcription of the UCP1 gene in their adipose tissue during a critical developmental stage. While marsupials possess genes commonly found in brown fat, the UCP1 protein in marsupials does not produce heat, indicating a lack of thermogenic function in their brown adipose tissue. This distinction underscores the evolutionary differences between marsupials and placental mammals in terms of heat production and regulation.
Analyzing UCP1 sequence information from various species, the researchers reconstructed the ancient UCP1 protein of the stem placental mammal from approximately 110 million years ago. This ancient protein demonstrated the ability to generate heat, suggesting the presence of heat-producing brown fat in the ancestor of placental mammals.
Understanding the evolution and function of brown fat is crucial for developing interventions to address metabolic disorders and improve human health. By studying the mammalian family tree and unraveling the mysteries of brown fat, researchers can gain valuable insights into the evolutionary history of mammals and the role of brown fat in regulating body temperature and metabolism.
**Keywords: marsupials, brown fat, mammalian evolution, UCP1 protein, metabolic diseases**
For more information, you can refer to the original research article published in Science by Susanne Keipert et al. (2024).