Cryo_READ is a computational tool using deep learning to automatically build full DNA/RNA atomic structure from cryo-EM map.
Copyright (C) 2022 Xiao Wang, Genki Terashi, Daisuke Kihara, and Purdue University.
License: GPL v3. (If you are interested in a different license, for example, for commercial use, please contact us.)
Contact: Daisuke Kihara (dkihara@purdue.edu)
For technical problems or questions, please reach to Xiao Wang (wang3702@purdue.edu).
Xiao Wang, Genki Terashi & Daisuke Kihara. De novo structure modeling for nucleic acids in cryo-EM maps using deep learning. Nature Methods, 2023. https://www.nature.com/articles/s41592-023-02032-5
@article{wang2023CryoREAD,
title={De novo structure modeling for nucleic acids in cryo-EM maps using deep learning},
author={Xiao Wang, Genki Terashi, and Daisuke Kihara},
journal={Nature Methods},
year={2023}
}
Apr 2024: CryoREAD includes a new model to support DNA/RNA structure modeling for input maps from 5-10A. The model is trained with maps at resolution 5-10A, and it will be used in CryoREAD once the input resolution is 5-10A.
Server(Recommended): https://em.kiharalab.org/algorithm/CryoREAD
Google Colab: https://bit.ly/CryoREAD
Step-by-step instructions are available. Limited by redistribution constraints of Coot and Phenix, the structure here is not refined and may include atom clashes. If you want better structure, please use our server or Github. For free user, colab has 4-hour running time limit and may not work for large structure(>=1000 nucleotides).
It provides two additional supports:
1. Detection Output: This option outputs probability values of detected phosphate, sugar, base, and base types, computed by deep learning, in the map, for users reference.
2. Refinement pipeline: structures from other source can be refined in the specified EM map.
Project website: https://kiharalab.org/emsuites
Detailed pipeline instructions can be found https://kiharalab.org/emsuites/cryoread.php
CryoREAD algorithm video (20 minutes): https://www.youtube.com/watch?v=p7Bpou2vL6o
For benchmark purpose, please check the eval_code for predicted structure evaluation.
Cryo_READ is a computational tool using deep learning to automatically build full DNA/RNA atomic structure from cryo-EM map.
DNA and RNA play fundamental roles in various cellular processes, where the three-dimensional (3D) structure provides critical information to understand molecular mechanisms of their functions. Although an increasing number of structures of nucleic acids and their complexes with proteins are determined by cryogenic electron microscopy (cryo-EM), structure modeling for DNA and RNA is still often challenging particularly when the map is determined at sub-atomic resolution. Moreover, computational methods are sparse for nucleic acid structure modeling.Here, we developed a deep learning-based fully automated de novo DNA/RNA atomic structure modeling method, CryoREAD. CryoREAD identifies phosphate, sugar, and base positions in a cryo-EM map using deep learning, which are traced and modeled into a 3D structure. When tested on cryo-EM maps determined at 2.0 to 5.0 Å resolution, CryoREAD built substantially accurate models than existing methods. We have further applied the method on cryo-EM maps of biomolecular complexes in SARS-CoV-2.
- Structure Detection by deep neural network CryoREAD networks;
- Tracing backbone according to detections;
- Fragment-based nucleotide assignment;
- Full atomic structure modeling.
CPU: >=8 cores
Memory (RAM): >=50Gb. For maps with more than 3,000 nucleotides, memory space should be higher than 200GB if the sequence is provided.
GPU: any GPU supports CUDA with at least 12GB memory.
GPU is required for CryoREAD and no CPU version is available for CryoREAD since it is too slow.
Python 3 : https://www.python.org/downloads/
Phenix: https://phenix-online.org/documentation/install-setup-run.html
Coot: https://www2.mrc-lmb.cam.ac.uk/personal/pemsley/coot/
Pymol (for map visualization): https://pymol.org/2/
Chimera (for map visualization): https://www.cgl.ucsf.edu/chimera/download.html
1. Install git
git clone https://github.com/kiharalab/CryoREAD.git && cd CryoREAD
You have two options to install dependency on your computer:
3.2.1 install anaconda.
Make sure you are in the CryoREAD directory and then run
conda env create -f environment.yml
Each time when you want to run this software, simply activate the environment by
conda activate CryoREAD
conda deactivate(If you want to exit)
3.2.1install pip.
pip3 install -r requirements.txt --user
If you encounter any errors, you can install each library one by one:
pip3 install biopython
pip3 install numpy
pip3 install numba
pip3 install scipy
pip3 install ortools
pip3 install mrcfile
pip3 install torch==1.6.0
To verify phenix is correctly installed for final refinement step, please run
phenix.real_space_refine -h
To veryify coot is correctly installed for final refinement step, please run
coot
If it can print out the help information of this function, then the refinemnt step of our program can be supported. If not, please always remove --refine command line in all the commands, then CryoREAD should output structure without refinement.
Command Parameters
usage: main.py [-h] [-F F] [-M M] [-P P] --mode MODE [--contour CONTOUR] [--stride STRIDE] [--box_size BOX_SIZE] [--gpu GPU] [--batch_size BATCH_SIZE] [-f F] [-m M]
[-g G] [-k K] [-R R] [--rule_soft RULE_SOFT] [--frag_size FRAG_SIZE] [--frag_stride FRAG_STRIDE] [--top_select TOP_SELECT] [--resolution RESOLUTION]
[--num_workers NUM_WORKERS] [--prediction_only PREDICTION_ONLY] [--no_seqinfo NO_SEQINFO]
optional arguments:
-h, --help show this help message and exit
-F F Input map file path. (str)
-M M Pre-trained model path. (str) Default value: "best_model". If you want to reproduce the results in our paper, your can specify "best_model_paper". Here the default path is the new model trained on the entire dataset.
-P P Optional fasta sequence file path. (str)
--mode MODE Control Mode for program: 0: cryo_READ structure modeling. Required parameter. (Integer), Default value: 0
--contour CONTOUR Contour level for input map, suggested 0.5*[author_contour]. (Float), Default value: 0.0
--stride STRIDE Stride for scanning of deep learning model. (Integer), Default value: 16.
--box_size BOX_SIZE Input box size for deep learning model. (Integer), Default value: 64
--gpu GPU Specify the gpu we will use. (str), Default value: None.
--batch_size BATCH_SIZE
Batch size for inference of network. (Integer), Default value: 4.
-f F Filter for representative points, for LDPs, removing points' normalized density<=-f (Float), Default value: 0.05
-m M After meanshifting merge points distance<[float]. (Float), Default value: 2.0.
-g G Bandwidth of the Gaussian filter, (Float), Default value: 3.0.
-k K Always keep edges where d<k parameter. (Float), Default value: 0.5
-R R Maximum length of local edges. (Float), Default value: 10.0.
--rule_soft RULE_SOFT
Use strict/soft rules to assemble collected fragments in DP step. (Integer), Default value: 0 (strict rules)
--frag_size FRAG_SIZE
Fragment size for sequence split.(Integer), Default value: 20
--frag_stride FRAG_STRIDE
Frag stride step. (Integer), Default value: 2
--top_select TOP_SELECT
Select top fragment candidate here. (Integer), Default value: 20
--resolution RESOLUTION
resolution of maps, used for final structure refinement. (Float), Default value: 2.5
--num_workers NUM_WORKERS
number of workers to fetch data for GPU inference. (Integer), Default value: 4
--prediction_only PREDICTION_ONLY
Optional input. Only run the deep learning prediction step. (True/False) Default value: False
--no_seqinfo NO_SEQINFO
Optional input. Build structures when no sequence information is available. (True/False) Default value: False
--thread THREAD
Use multiple threads for fragment-based sequence assignment,default:1 (multi-threading is disabled)
DNA/RNA structure modeling without FASTA sequence
python3 main.py --mode=0 -F=[Map_Path] -M=[Model_Path] --contour=[half_contour_level] --gpu=[GPU_ID] --batch_size=[batch_size] --resolution=[Map_Resolution] --no_seqinfo --refine
[Map_Path] is the path of the experimental cryo-EM map,
[Model_Path] is the path of our pre-trained deep learning model, (If you want to reproduce the results in our paper, your can specify "best_model_paper". Here the default path is the new model trained on the entire dataset.)
[half_contour_level] is 0.5* contour_level (suggested by author) to remove outside regions to save processing time,
[GPU_ID] specifies the gpu used for inference,
[batch_size] is the number of examples per batch in the inference (we used 8 with a 24GB GPU),
[Map_Resolution] is the resolution of the deposited maps.
"--refine" should be removed if you can not successfully install Phenix/coot correctly, which may result in nucleotides that do not satisfy some geometry and chemical constraints.
The automatically build atomic structure is saved in [Predict_Result/(map-name)/CryoREAD_noseq.pdb] (or [Predict_Result/(map-name)/CryoREAD_norefine.pdb] if you do not add --refine param) in pdb format. You can also add --output=[your_directory] to specify the output directory. Then the output will be saved in [output_dir/CryoREAD_noseq.pdb].
python3 main.py --mode=0 -F=example/21051.mrc -M=best_model --contour=0.3 --gpu=0 --batch_size=4 --resolution=3.7 --no_seqinfo --refine
DNA/RNA structure modeling with FASTA sequence
python3 main.py --mode=0 -F=[Map_Path] -M=[Model_Path] -P=[Fasta_Path] --contour=[half_contour_level] --gpu=[GPU_ID] --batch_size=[batch_size] --rule_soft=[assignment_rule] --resolution=[Map_Resolution] --refine --thread=[num_threads]
[Map_Path] is the path of the experimental cryo-EM map,
[Model_Path] is the path of our pre-trained deep learning model, (If you want to reproduce the results in our paper, your can specify "best_model_paper". Here the default path is the new model trained on the entire dataset.)
[Fasta_Path] is the path of the input fasta file about sequence information,
[half_contour_level] is 0.5* contour_level (suggested by author) to remove outside regions to save processing time,
[GPU_ID] specifies the gpu used for inference,
[batch_size] is the number of examples per batch in the inference (we used 8 with a 24GB GPU),
[rule_soft] specifies the assignment rule, default is 0 to use the strict assignment assembling rule,
[Map_Resolution] is the resolution of the deposited maps.
[num_thread] specifies the number of CPUs used for fragment-based sequence assignment.
"--refine" should be removed if you can not successfully install Phenix/coot correctly,which may result in nucleotides that do not satisfy some geometry and chemical constraints.
python3 main.py --mode=0 -F=example/21051.mrc -M=best_model -P=example/21051.fasta --contour=0.3 --gpu=0 --batch_size=4 --rule_soft=0 --resolution=3.7 --refine --thread 4
The automatically build atomic structure is saved in [Predict_Result/(map-name)/CryoREAD.pdb] in pdb format (or [Predict_Result/(map-name)/CryoREAD_norefine.pdb] if you do not add --refine param). Modeled structures without considering sequence information are also saved as [Predict_Result/(map-name)/Output/CryoREAD_noseq.pdb] (without refinement). Meanwhile, structures only considering the sequence information without connecting gap regions are saved in [Predict_Result/(map-name)/Output/CryoREAD_seqonly.pdb] (without refinement) for reference.
Please adjust --thread based on your available CPU numbers (more is better).
CryoREAD detection (if you only want to check detection by deep learning)
python3 main.py --mode=0 -F=[Map_Path] -M=[Model_Path] --contour=[half_contour_level] --gpu=[GPU_ID] --batch_size=[batch_size] --prediction_only
[Map_Path] is the path of the experimental cryo-EM map,
[Model_Path] is the path of our pre-trained deep learning model, (If you want to reproduce the results in our paper, your can specify "best_model_paper". Here the default path is the new model trained on the entire dataset.)
[half_contour_level] is 0.5* contour_level (suggested by author) to remove outside regions to save processing time,
[GPU_ID] specifies the gpu used for inference,
[batch_size] is the number of examples per batch in the inference (we used 8 with a 24GB GPU).
The predicted probability maps are saved in [Predict_Result/(map_name)/2nd_stage_detection] with mrc format. It will include 8 mrc files corresponding to 8 different classes.
python3 main.py --mode=0 -F=example/21051.mrc -M=best_model --contour=0.3 --gpu=0 --batch_size=4 --prediction_only
Structure Refinement Pipeline in CryoREAD (if you only want to refine your structure)
The full refinement pipeline involving Phenix and coot is also available for refinement-only purposes.
python3 main.py --mode=1 -F=[input_structure_pdb] -M=[input_map_path] -P=[output_dir] --resolution=[resolution]
This refinement pipeline can work for any given structure (not limited to DNA/RNA) and a corresponding map.
[input_structure_pdb] is the path of the input structure in pdb format,
[input_map_path] corresponds to the input map path.
[output_dir]: the directory you specify to save the outputs during refinement process. The final output Refine_cycle3.pdb will be generated in this directory.
[resolution] is the resolution of the deposited maps.
python3 main.py --mode=1 -F=example/6v5b_drna.pdb -M=example/21051.mrc -P=refine_test --resolution=3.7
This will refine the input structure according to density and output the refined structure in [refine_test] directory.
Structure Evaluation in CryoREAD (if you only want to compare your predicted structure with native structure)
We provided the evaluation pipeline used in CryoREAD, use 5Å as a cutoff. Different from Phenix, we matched the nucleotides based on the average distance of the backbone atoms of nucleotides instead of only using P atoms, which is not so stable and accurate.
To use our evaluation pipeline, please use
python3 main.py --mode=2 -F=predicted.cif[.pdb] -M=target.cif[.pdb]
Here -F takes the predicted pdb/cif file and -M takes the native pdb/cif files. The example output is as follows
****************************************************************************************************
Atom Coverage: 0.940 Atom Precision: 0.872
Sequence Recall(Match): 0.600 Sequence Precision(Match): 0.562
Sequence Recall: 0.564 Sequence Precision: 0.490
RMSD: 3.010
****************************************************************************************************
All the reported metrics in our paper can be calculated.
Atom Coverage is computed as the fraction of sugar atoms (C1′, C2′, O2′ for RNA, C3′, O3′, C4′, O4′, C5′) and phosphate atoms (P, OP1, OP2, O5′, OP3′) that were closer than 5 Å to a matched sugar or phosphate node for each nucleotide, which were then averaged over all the nucleotides in the map. Atom Precision is computed as the fraction of nodes within 5 Å to the corresponding atoms of its closest nucleotides.
A cutoff of 5 Å was used because it is shorter than the average distance between adjacent phosphate atoms, which is 6.0 Å.
Sequence recall is computed by identifying a nucleotide in the model that corresponds to each nucleotide in the reference structure. This identification is done by assigning the nucleotide in the model that has the closest average atom distance to each nucleotide in the reference structure. Then, it is determined whether the bases are identical. Finally, the fraction of identical bases over all the bases in the reference structure is computed.
Sequence recall (match) only considers nucleotides in the reference structure that have a corresponding nucleotide in the model (an average atom pair distance of less than 5 Å).
Sequence precision is defined as the fraction of the identical bases over all the bases in the model.
Sequence precision (match) only considers nucleotides in the model structure that have a corresponding nucleotide in the reference (an average atom pair distance of less than 5 Å).
RMSD is calculated between backbone atoms of nucleotides in the model structure that have a corresponding nucleotide in the reference.
For a comprehensive assessment, it is important to use multiple metrics to evaluate the accuracy of DNA/RNA structure modeling. Each metric provides different aspects of the modeling performance.
Cryo-EM map with mrc format. (Optional) Sequence information with fasta format. Our example input can be found here
1 *.mrc: a mrc file saved our detected probabilites by our deep learning model.
2 *.pdb: a PDB file that stores the atomic DNA/RNA structure by our method.
Our example output can be found here. All the intermediate results are also kept here.