An Introduction to Molecular Evolutionary Analysis with NCBI Datasets and Python

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An Introduction to Molecular Evolutionary Analysis with NCBI Datasets and Python

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This workshop concluded on July 21, 2022. The workshop materials are available here

As they diverge from a common ancestor, species accumulate differences in their DNA sequences. Differences within a protein-coding region are classified in two types. Non-synonymous substitutions change the amino acid sequence of the protein, while synonymous substitutions do not. Synonymous substitutions are largely invisible to natural selection and tend to accumulate at a constant rate. On the other hand, non-synonymous substitutions whose effects are beneficial accumulate at a faster rate, while those that are deleterious are suppressed. By comparing the rates of non-synonymous and synonymous substitutions, we can infer whether natural selection has primarily acted to conserve the protein sequence or to adapt it to a new environment or function.

In this workshop you will learn to compare the protein-coding sequences of two species to estimate which proteins show signs of adaptation. Working in a Jupyter notebook with bash and Python, you will use the NCBI Datasets command line interface (CLI) to download sequence data, then perform analysis with a few popular Python packages. The workshop assumes basic familiarity with a scripting language such as Python or R at a level equivalent to a semester course or programming bootcamp.

In this workshop, you will learn how to:

  • Search for and download protein ortholog sequences with NCBI Datasets CLI
  • Parse the downloaded files with BioPython
  • Identify synonymous and non-synonymous substitutions and calculate substitution rates
  • Plot the results with Matplotlib

 

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Event registration closed.
 

Date And Time

2022-07-21 @ 01:00 PM to
2022-07-21 @ 04:00 PM
 

Registration End Date

2022-07-04
 

Location

Online event
 

Event Types

 

Event Category

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