Venkatesh Lab

GAL regulation in S. cerivisae

 

Evolutionary success of an organism depends on its ability to express or adapt to constantly changing environmental conditions. Saccharomyces cerevisiae has evolved an elaborate genetic circuit to regulate the expression of galactose-metabolizing enzymes in the presence of galactose but in the absence of glucose. The circuit possesses molecular mechanisms such as multiple binding sites, cooperativity, autoregulation, nucleocytoplasmic shuttling, and substrate sensing mechanism. Furthermore, the GAL system consists of two positive (activating) feedback and one negative (repressing) feedback loops. These individual mechanisms, elucidated through experimental approach, can be integrated to obtain a system-wide behavior. Mathematical models in conjunction with guided experiments have demonstrated system-level properties such as ultrasensitivity, memory, noise attenuation, rapid response, and sensitive response arising out of the molecular interactions. These system-level properties allow S. cerevisiae to adapt and grow in a galactose medium under noisy and changing environments. This review focuses on system-level models and properties of the GAL regulon.

PUBLICATIONS

 

Stochastic galactokinase expression underlies GAL gene induction in a GAL3 mutant of Saccharomyces cerevisiae,

RK Kar, M Qureshi, AK DasAdhikari, T Zahir, KV Venkatesh, PJ Bhat, FEBS Journal 281 (7), 1798-1817, 2014.

 

GAL regulon of Saccharomyces cerevisiae performs optimally to maximize growth on galactose

P Malakar, KV Venkatesh, FEMS yeast research, 14 (2), 346-356, 2014

 

Growth Related Model Of the Gal System In Saccharomyces Cerevisiae Predicts Behavior Of Several Mutant Strains

Pannala Venkat, Hazarika Saumar, Bhat P Bhartiya Sharad, K V Venkatesh, IET Systems Biology, 2012.

 

Characterizing the Memory of the GAL Regulatory Network in Saccharomyces cerevisiae

Vishwesh V. Kulkarni, Venkatesh Kareenhalli, Ganesh A. Viswananthan, Marc Riedel, Systems and Synthetic Biology, 2011

 

Dynamic Analysis of the KlGAL Regulatory System in Kluyveromyces lactis: A Comparative Study with Saccharomyces cerevisiae

Venkat R. Pannala, Sharad Bhartiya and K. V.Venkatesh, Systems and Synthetic Biology, 2011

 

Experimental and Steady State analysis of the GAL regulatory system in Kluyveromyces lactis

 Venkat R. Pannala, Sharad Bhartiya and K. V.Venkatesh , FEBS Journal, 277, 2987 ? 3002, 2010.

 

Stability analysis of the GAL regulatory network in Saccharomyces cerevisiae and Kluyveromyces lactis

Vishwesh Kulkarni, K. V. Venkatesh, Pushkar Malakar, Lucy Y Pao, Michael Safonov and Ganesh Viswanathan, BMC Bioinformatics 2010, 11(S43)

 

Experimental and Steady State Analysis of the GAL Regulatory System in Kluyveromyces lactis

Venkat Reddy Pannala, Sharad Bhartiya and K.V.Venkatesh, FEBS, 2010.

 

Stability analysis of the GAL regulatory network in Saccharomyces cerevisiae and Kluyveromyces lactis,

Vishwesh Kulkarni, K. V. Venkatesh, Pushkar Malakar, Lucy Y Pao, Michael Safonov and Ganesh Viswanathan, BMC Bioinformatics, 11 (S43) 2010.

 

Systems Biology of GAL Regulon in Saccharomyces cerevisiae

Venkat RP, PJ Bhat, Sharad Bhartiya, KV Venkatesh,  Wiley Interdisciplinary, Reviews: Systems Biology and Medicine, 2009

 

Stochastic analysis of the GAL genetic switch in Saccharomyces cerevisiae: Modeling and experiments reveal hierarchy in glucose repression,

Vinay Prasad, K V Venkatesh, BMC Systems Biology, 2:97, 2008.

 

Stochastic variation in the concentration of a repressor activates GAL genetic switch: Implications in evolution of regulatory network

P J Bhat and K V Venkatesh, FEBS Letters, [579] (3), 597-603, 2005.

 

Autoregulation of Regulatory Proteins is Key for Dynamic Operation of GAL Switch in Saccharomyces cerevisiae

Anurag Ruhela, Malkhey Verma, Jeremy S. Edwards, P. J. Bhat, Sharad Bhartiya and KV Venkatesh, FEBS Letters, [576] (1), 119-126, 2004

 

A Steady State Modeling Approach to Validate in vivo Mechanism of GAL Regulatory Network in Saccahromyces cerevisiae

Malkhey Verma, PJ Bhat, Sharad Bhartiya and KV Venkatesh, European Journal of Biochemistry, [271] (20), 4064-4074, 2004.

 

Expression of GAL genes in a mutant strain of Saccharomyces cerevisae lacking GAL80: Quantitative Model and Experimental Verification

Malkhey Verma, PJ Bhat and KV Venkatesh, Biotechnology and Applied Biochemistry [39] (1),89-97, 2004.

 

Quantitative analysis of GAL genetic switch of Saccharomyces cerevisiae reveals that nucleocytoplasmic shuttling of Gal80p results in a highly sensitive response to galactose

Malkhey Verma, P. J. Bhat, and K. V. Venkatesh, The Journal of Biological chemistry, [278] (49), 48764-48769, 2003 .

 

Quantitative Model for Gal4p Mediated expression of the Galactose/Melibiose Regulon in Saccaharomyces cerevisiae

KV Venkatesh, PJ Bhat, RA Kumar and Pankaj Doshi, Biotechnology Progress, [15] (1), 51-57, 1999.