iCn3D, a web-based 3D viewer for sharing 1D/2D/3D representations of biomolecular structures
Related Experiment Video
Updated: Jan 23, 2026

3D Printing of Biomolecular Models for Research and Pedagogy
Published on: March 13, 2017
Jiyao Wang1, Philippe Youkharibache1,2, Dachuan Zhang1
1National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA.
Motivation:
Build a web-based 3D molecular structure viewer focusing on interactive structural analysis.
Results:
iCn3D (I-see-in-3D) can simultaneously show 3D structure, 2D molecular contacts and 1D protein and nucleotide sequences through an integrated sequence/annotation browser. Pre-defined and arbitrary molecular features can be selected in any of the 1D/2D/3D windows as sets of residues and these selections are synchronized dynamically in all displays. Biological annotations such as protein domains, single nucleotide variations, etc. can be shown as tracks in the 1D sequence/annotation browser. These customized displays can be shared with colleagues or publishers via a simple URL. iCn3D can display structure-structure alignments obtained from NCBI's VAST+ service. It can also display the alignment of a sequence with a structure as identified by BLAST, and thus relate 3D structure to a large fraction of all known proteins. iCn3D can also display electron density maps or electron microscopy (EM) density maps, and export files for 3D printing. The following example URL exemplifies some of the 1D/2D/3D representations: https://www.ncbi.nlm.nih.gov/Structure/icn3d/full.html?mmdbid=1TUP&showanno=1&show2d=1&showsets=1.
Availability And Implementation:
iCn3D is freely available to the public. Its source code is available at https://github.com/ncbi/icn3d.
Supplementary Information:
Supplementary data are available at Bioinformatics online.
Related Concept Videos
Control Volume and System Representations
The control volume approach considers a stationary region in space through which fluid flows. This region is bounded by a control surface. For instance, in the case of water...
State Space Representation
Consider an RLC circuit, a...
Graphical and Analytic Representation of Sinusoids
The first step is measuring the peak-to-peak value, which is twice the amplitude of the sinusoid. This provides information about the maximum voltage swing of the waveform.
Secondly, the period and angular frequency are determined. The period is the time taken for one complete cycle of the waveform, while...
Vector Representation of Complex Numbers
Consider a function defined as the product of the complex factors in the numerator divided by the product of the complex factors in the...
Covalent Bonding and Lewis Structures
Two-Dimensional (2D) NMR: Overview
The first step is the preparation period, during which nucleus A is excited with a radiofrequency pulse....

