English sottotitoli

← Unlocking DNA: The Center for Comparative Genomics

How the Center for Comparative Genomics unravels the secrets of DNA, helping us to understand evolutionary biology and its potential impact for new medical applications.

Ottieni il codice di inserimento
27 Lingue

Mostrare Revisione 9 creata 03/02/2020 da Cesslator.

  1. ♪ (music) ♪
  2. Probably the most
    appealing part for me was
  3. answering these long-standing questions
    that I've had since I was a kid.
  4. Evolutionary biology helps us
    understand the nature around us.
  5. First and foremost,
    I'm interested in evolutionary questions.
  6. I'm very interested in the biodiversity
    that we see on Earth.
  7. Everything from species identification
    to deep, evolutionary questions
  8. can be addressed with DNA,
  9. and the CCG provides
    all of the resources necessary.
  10. So if someone's out collecting birds
    or reptiles or whatever,
  11. they bring it to the lab
    and extract the DNA.
  12. They purify the DNA,
    separate all the cell material from it,
  13. and then you have pure DNA.
  14. Once you have pure DNA,
    you can do all kinds of things with it.
  15. You can sequence that gene
    for many different organisms,
  16. then compare them to each other
    and build an evolutionary history,
  17. or a "family tree" for genes and species.
  18. For the past 30 years,
  19. the main platform for sequencing,
    is Sanger sequencing.
  20. With that method we look
    at one section of the genome at a time.
  21. With next-gen sequencing methods,
  22. the data we can get
    is massively increased
  23. because we can do a lot of
    the sequencing in parallel.
  24. We have the MiSeq
    sequencing machine here,
  25. and we can produce
    25 million sequences in one read.
  26. More recently there is
    a third generation sequencing.
  27. Here we have
    an Oxford Nanopore MinION machine.
  28. So, by reading those electrical signals,
    we're able to read the DNA.
  29. It fits in my pocket. It's amazing.
  30. (laughs)
  31. Matt Van Dam is currently
    working on weevils,
  32. using this new technology to try
    to understand their evolutionary history.
  33. Weevils are
    a particular family of beetles.
  34. One of the problems,
    in the genome assembly,
  35. is that you have
    all these little bits of information.
  36. And then, sometimes,
  37. sticking them together
    in the right way is extremely complicated.
  38. The Nanopore does quite well
    for these longer reads.
  39. A group of us here, at the Academy,
    are sequencing
  40. the complete genome
    of the Pygmy Angelfish.
  41. And that includes all of the chromosomes,
    all of the mitochondria, and everything.
  42. It's very exciting work.
  43. Lauren is trying to look at
    which genes are active or turned on,
  44. and what kind of combinations
    can be produced by these different genes
  45. being turned on and off.
  46. One of the craziest things is
  47. we've only characterized
    like 1% of scorpion venoms.
  48. A single individual scorpion might have
  49. 150 unique types of venom
    in its venom gland.
  50. And so it has genes to create
    all of these different venoms,
  51. and those venoms are highly specific.
  52. There's active research
    on using scorpion venom
  53. to treat cancer, to treat arthritis,
    to treat multiple sclerosis.
  54. So she is using something
    called RNA-Seq or transcriptomics,
  55. and what you do is
    you sequence all of the proteins.
  56. That's a way to sort of
    skip the whole genome sequencing
  57. and you can focus just on the RNA,
    which is what produces the proteins.
  58. I've been involved with
    the seahorse project, for many years.
  59. We've been trying to understand
    this very complex group.
  60. They apparently evolved very rapidly
    and created many different forms,
  61. so we have seahorses,
    pipefish, sea dragons,
  62. all these wild looking fish,
    and nobody really knows the relationships
  63. because they evolved
    and radiated very rapidly
  64. and in a very short period of time.
  65. We're using a new technology
    called ultra-conserved elements,
  66. and these are parts of
    the genome that are unchanged
  67. across hundreds of millions of years
    to reconstruct those branches.
  68. Our exhibits have lots of amphibians,
  69. so when we bring them in,
    we have to make sure
  70. that we don't spread chytrid fungus
    to the rest of the others.
  71. If we put it in
    with the rest of the exhibits,
  72. they would probably all die.
  73. We essentially create these probes,
    which are pieces of DNA
  74. that match those unique markers
    to the chytrid fungus.
  75. If the probe matches,
    we know it has this fungus.
  76. If there's no match, we can pretty be sure
    that there are no fungus infections.
  77. I think that the role of the CCG
  78. is to help every scientist
    answer their questions.
  79. And there are very few questions
    you can address without genetic data.
  80. We have all of this information,
    that's accumulated for decades
  81. by scientists and naturalists,
  82. and they're depositing it
    in our collection
  83. with very good ecological data
    that's associated with it.
  84. It's very important
    that we can also unlock that knowledge.
  85. ♪ (music) ♪