Noise Filtering in Biological Networks
In biology, networks serve as powerful representations of systems across various scales, from genetic interactions (GI) in organisms to food webs in ecological communities. However, biological networks are often plagued by multiple sources of error, including measurement inaccuracies, sampling biases, and incomplete data. While sophisticated algorithms have been developed to address these challenges, yielding notable successes [1], existing methods fail to fully exploit the rich second-moment statistical information (variances and covariances) present in biological data. Filling this gap requires methodological advancements. We develop a network version of the generalized Wiener filter [2], specifically tailored for filtering edge noise in biological networks. The core technical obstacle arises from the absence of a natural distance metric in network
settings, distinguishing this task from traditional signal and image processing applications. Depending on the scenario, we resolve this issue by either uncovering the complete covariance structure of the network data or employing a network theoretic ansatz.
Team Members
Mark Zhao
István A. Kovács
Figure 1: Original (left) and filtered (right) GI profile similarity networks for the essential genes of the yeast
Saccharomyces cerevisiae, highlighting regions associated with microtubule nucleation using SAFE [3].
As an application of broad implications, we apply our approach to a state-of-the-art genetic interaction (GI)
network mapped for the yeast Saccharomyces cerevisiae [4], which includes approximately 120,000 interactions
between pairs of around 900 essential genes. The resulting filtered GI network exhibits greater symmetry and offers
potential advantages in gene function prediction and other downstream analyses, suggesting the effectiveness of
our method for biological discovery. This work paves the way for further exploration into advanced noise-filtering
techniques in biological networks.
We acknowledge support from the National Institute for Theory and Mathematics in Biology through the National
Science Foundation (grant number DMS-2235451) and the Simons Foundation (grant number MP-TMPS-
00005320).
References​
[1] Bo Wang, Armin Pourshafeie, Marinka Zitnik, Junjie Zhu, Carlos D Bustamante, Serafim Batzoglou, and Jure
Leskovec. Network enhancement as a general method to denoise weighted biological networks. Nature
communications, 9(1):3108, 2018.
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[2] William K Pratt. Generalized wiener filtering computation techniques. IEEE Transactions on Computers, 100(7):636–
641, 1972.
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[3] Anastasia Baryshnikova. Systematic functional annotation and visualization of biological networks. Cell systems,
2(6):412–421, 2016.
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[4] Michael Costanzo, Benjamin VanderSluis, Elizabeth N Koch, Anastasia Baryshnikova, Carles Pons, Guihong Tan, Wen Wang, Matej Usaj, Julia Hanchard, Susan D Lee, et al. A global genetic interaction network maps a wiring diagram of cellular function. Science, 353(6306):aaf1420, 2016.