Welcome to Tutorials Section for MetagenoNets

Here we have attempted to provide you with precise guidelines for using MetagenoNets. You can use the left menu to fast-scroll across the content. .

Why MetagenoNets?

Motivation
Microbial association networks (often termed as Co-occurence networks) are very frequently used in Microbiome research to understand community dynamics (or interactions). Inferring any biological network and obtaining relevant biological insights however requires a lengthy workflow of data management, choice of appropriate methods, statistical computations, information analysis, followed by an entirely different pipeline for suitably visualizing, reporting and comparing the interactions. This complexity of workflow is further increased with the added dimension of multi-class and multi-group 'Meta Data' often associated with Microbiome studies, thereby giving rise to a need for not only classified networks, but also integrated and bipartite networks. The plethora of correlation analysis methods ranging from simplistic Pearson, Spearman, Kendall etc. to statistically intensive methods like ReBoot, CCREPE, SPARCC and NAMAP further increase the amount of effort required to perform correlation based microbiome interaction studies.

To date, there is a high dependency on stand-alone generic softwares, plugins, locally installed programs (with a series of dependencies), knowledge of scripting/ programming languages for accomplishing the task of a meaningful microbiome network analysis. Limited number of web applications available in this space are either too specialized for other research areas or offer minimal functionalities. A comprehensive tool (especially a web-server) that may circumvent most of these bottlenecks, would be highly useful to the researchers at large.

Features in MetagenoNets

MetaNets as a Solution
We present MetagenoNets web-server as an effort towards easing the process of inferring and analyzing correlation driven microbial association networks. Following features of MetagenoNets are expected to be of significant value addition to the space of microbiome network analysis:

(a) Accepts all types of small to large microbial feature tables along with multi-level meta-data. Provision for secondary feature tables allows deeper insights for an integrated analysis (as described later in this tutorial).
(b) Offers frequently used data normalization startegies (TSS, CSS, Quartile) and transformation strategies (DeSeq2, TMM, CLR)
(c) Provision for feature reduction through prevalence and occurence based filters
(d) Comprehensive offering of major state of art correlation driven network inference methods (i) SPARCC (ii) ReBoot (iii) CCREPE (iv) NAMAP, alongwith bootstrapped and classical versions of approaches based on Pearson and Spearman coefficient.
(e) Intelligent categorization of Meta-data into categorical and continous data types, thereby allowing the end-user to automatically correlate continous meta-data with primary feature set through integrated and bi-partite networks (as described later).
(f) Three types of network generation options (i) class or group respective individual networks (ii) meta-data and/or secondary data integrated networks (iii) bi-partite networks, thereby enabling a comprehensive use of abundance datasets as well as associated meta-data
(g) Interactive visualizations for networks and network properties
(h) Set based comparisons of categorical meta-data driven network groups through interactive Venn Diagrams and network graphs of the intersections
(j) Easy to use user inter-face and modern web-design approach for seamless experience at the front-end

MetagenoNets facilitates end-users to concomitantly infer, statistically analyse, and compare correlation driven microbial association networks, and in the process generate a plethora of intuitive self-explanatory visual outputs in an automated fashion.

Input Data and Meta Data Formats

Input Data for MetagenoNets

MetagenoNets accepts two types of input data, (i) Primary Input Data (ii) Secondary Input Data

Primary input data is essentially a multivariate abundance table representing abundances of various operational taxonomic units (OTUs) obtained from various de-novo or reference based taxonomic classifiers. It should be a tab-separated file, wherein first row pertains to the samples in the data, and first column pertains to the taxa (or classified microbes) in the data. It is mandatory to provide a Primary Input Data to MetagenoNets.

Secondary input data is an optional input data type, that is also a multivariate abundance table. However, this input table may contain any feature matrix (like Pathway abundances, Metabolite abundances, Continous Data of any kind) for the samples provided in the primary input data. This feature set is used for finding relevant set of co-variates against the primary feature set. The co-variates are thereafter visualized in 'integrated' as well as 'bi-partite' networks, as preferred by the end-user.

Meta Data for MetagenoNets

Meta data for MetagenoNets is a tab-separated file containing multiple columns of sample information. First row contains the names of various meta data classes, while first column contains the names of the samples (as present in the input data).

Each column of meta data file, representing various classes of environments, contains the names of various sub-classes in each environment.

It is pertinent to note that MetagenoNets automatically infers the categorical and continous metadata types in the supplied meta-data file. The categorical data is offered to the end-user for creating various class-specific of networks, while continous data is offered to find co-variates in the primary and secondary input data feature set. The co-variates are visualized in the integrated as well as bi-partite networks.

Summarizing the Typical Format
More Tutorials

We hope that this documentation helped you in understanding MetagenoNets and its functionalities to some extent. You will find more assistance in each module of MetagenoNets through module specific plot guides and assistive tool tips in the dashboards. If there is any query that needs to be addressed, feel free to reach out to us at sunil.nagpal@tcs.com or sharmila.mande@tcs.com.

Thank you for your time and interest.