iGEM Distribution Design

This repository is for collective design of an iGEM DNA distribution. The processes used in this repository are intended to support:

• Design, review, and discussion by many contributors
• Keeping stable records of decisions
• Checking for errors and issues

Table of Contents

• Organization: Packages & Views
  • Package Directories
• Using the Package Spreadsheet
• Editing and Review

Organization: Packages & Views

Each directory contains one "package" of parts, where a "package" is a coherent collection of basic or composite parts and devices. Packages should be large enough to contain a full "tool kit", but small enough to be readily understood, reviewed, and discussed. Some examples of reasonable packages:

• a collection of small molecule sensors
• a system of recombinases and recombinase targets, plus some ready-to-use recombinase-based devices made with them
• A collection of terminators
• A set of transcriptional insulators and insulated parts and devices

It's OK for a part to appear in multiple packages. Multiple usages will be detected and only one copy will appear in the actual distribution.

Package Directories

The directory for a package should contain the following:

1. A package spreadsheet, following the format of package template.xlsx. This is the central file of the package and defines all of its contents. The format must not be altered, or else it cannot be processed correctly.
2. Files defining basic parts in SBOL3, SBOL2, GenBank, or FASTA format. These are optional and can be referred to by the package spreadsheet. Any given part must appear in only one of such files.
3. A views subdirectory, which contains exported versions of package data. These files should not be edited by hand. Views to expect are:
   • CSV exports from the package spreadsheet, to simplify review of differences in pull requests.
   • A compilation of all parts and libraries in the package encoded in SBOL. Not yet automated.
   • GenBank and FASTA versions of the package. These are lossy "flat" exports, since these formats can capture only individual sequence design, not part relationships or package and library structure. Not yet automated.

Package directories should not have any other subdirectories.

Using the Package Spreadsheet

The package spreadsheet allows a collection of related parts to be specified compactly.

The Parts and Devices tab list of all the parts that are to be used, along with notes about them as needed. In this context, "Part" or "Device" just means any contiguous DNA sequence that you don't need to subdivide, and can include multiple sequence features. For example J04450, which encodes a complete functional unit, could be entered as a single part/device on this sheet (subpart relationships will be detected later in the process, via sequence information).

DNA sequence information can be specified in three ways:

• Reference to the iGEM repository
• Reference to an ID in one of the directory files
• Direct listing in the sheet

The Libraries and Composite Parts tab contains "build plans" for how parts/devices will be combined. Three different types of combinations can be indicated here:

• A library of alternatives can be grouped together
• The vector backbones to carry parts can be selected
• Parts can be concatenated together into larger composite parts

The "final product" column indicates which of these are intended to be the actual plasmids in the distribution, as opposed to intermediates in the build plan.

Example: a line on this tab can indicate that we want all 20 Anderson promoters to be put into the pOpen_v4 and pSB1C3 backbones, as a final product

Columns in blue are optional; columns in black are required.

Some of the columns have constrained data values. You can add organisms to the organism columns by adding entries on the "Organism Terms" tab. Do not modify the other tabs; they are used for configuring spreadsheet's automation.

Editing and Review

To organize collective editing and review, this repository uses the GitFlow workflow. The key points for contributors to know are:

• The main branch is only for releases, and the develop branch only for approved and validated pre-release material. main should have very few commits, mostly just release tags.
• All proposed changes should be made on new branches off of develop.
  • Give your branch a short informative name like small-molecule-inducers or IP-free-fluorescence.
  • Example: You see some missing constructs in a sensors package and want to add them. First, you make a new add-missing-sensors branch off of develop. You edit the package Excel file to add the sensors, commit, and push. GitHub automatically creates CSV exports in the views directory for the package. Satisfied with what you see, you create a pull request and ask a colleague to review and merge.
• In order to incorporate a proposed change, make a pull request from the change branch into develop and request review from other contributors.
  • Make sure that your pull request includes a clear explanation of the nature of the contribution, the value of including it, and justification of the functionality of the parts.
  • No branch should be merged without an independent review that approves the pull request.
  • Automated validation checks make sure your contribution is well-organized. Do not merge any pull that is failing validation!
  • GitHub doesn't visualize Excel diffs well, so a GitHub action creates CSV exports to allow the change to be more easily reviewed and discussed.
• You can also further branch and pull request off of branches.
  • Example: somebody is working on a CRISPR-repressors branch, and you want suggest new composite constructs using their repressors. First, you make a new composite-CRISPR-repressors branch from their branch. You add your changes on that branch, then set up a pull request from composite-CRISPR-repressors into CRISPR-repressors and ask them to review your pull request.