#ScienceSaturday posts share exciting scientific developments and educational resources with the KAND community. Each week, Dr. Dominique Lessard and Dr. Dylan Verden of KIF1A.ORG summarize newly published KIF1A-related research and highlight progress in rare disease research and therapeutic development.
Effect of detachment of motor protein from track on its transport
KIF1A is known to be remarkable for two of its traits: Its fast movement and its hyperprocessivity (ability to move large distances) – KIF1A is a long-distance sprinter. However, recent evidence has also shown that KIF1A is slippery and likely to detach from its microtubule. So how does a motor that can’t stay on its track perform so well? In this week’s article, Dr. Rizvi from the Indian Institute of Technology Hyderabad in India used experimental data from other studies to model how motor protein speed and travel distance depend on its likelihood of detaching from a microtubule.
To do this, the author modeled two scenarios:
- A time-controlled test that estimates how far a motor protein can move in a certain amount of time.
- A distance-controlled test that estimates how long it takes a motor protein to move a certain distance.
When it was assumed that motor proteins’ likelihood of detaching doesn’t impact speed, these models failed to match past experimental data, which indicates the model was missing something. So the author updated their model to assume that the detachment probability and motor speed are related. This relationship makes sense – you can’t take a step if you don’t lift your foot from the ground, and the faster you walk the more times you must lift that foot.
The difference is that unlike a person, KIF1A isn’t held to a microtubule by gravity, and when it detaches it might just float away. For this reason, walking as fast as possible isn’t always the best way to carry cargo a long distance because each step carries a chance of floating away. Models predicted that in some cases a moderate pace made motor proteins more likely to reach their target distance.
These models are incomplete; they don’t take into account how good a motor protein is at reattaching, something KIF1A has been found to excel at in recent studies. However studies like this give us a better understanding of how differences in motor proteins facilitate different kinds of cargo transport. These are important considerations when assessing improved KIF1A transport in response to therapeutics.
Global Genes and Rare Disease Diversity Coalition Launch Next Phase of Multifaceted Partnership Aimed at Accelerating and Advancing Health Equity
There are a boggling amount of factors that go into our health, which can present a particular challenge for rare disease communities. The way genetic disorders manifest can vary between individuals, in part because they can be shaped by medical factors other family members have experienced – if my grandmother dealt with hypertension, that’s useful information for my own healthcare. Understanding the medical history of relatives can inform risk factors and health decisions for everyone, including rare disease patients.
This is the rationale behind the Know Your Family History Initiative by Global Genes and the Rare Disease Diversity Coalition, which is focusing on using family history to advance inclusive diagnosis and healthcare for rare disease patients in underserved and marginalized communities. The initiative provides resources to help families discuss and explore their shared medical history, which they can share with their healthcare provider.