Biology subjects

Willig, L.

Publications and source records attributed to Willig, L..

3 recordsLinked to original sources

bioRxiv2026

Weak interactions drive selective proteome demixing and tune the differential response to environmental perturbations

The intracellular space is a crowded environment where macromolecules perform distinct tasks despite pervasive "non-specific" interactions. Whether these interactions are functionally relevant and how they influence cellular organization remains unclear. Here, we developed QuPID-MS, which measures the propensity of proteins to phase separate in native cell extracts proteome-wide. We find that weak interactions drive condensation of half of the proteome in a crowding- and temperature-dependent manner and we present evidence that this proteome demixing occurs in cells. Importantly, protein condensation properties are conserved and broadly change when cells adapt to new environments, demonstrating that weak interactions are regulated and linked to function. Indeed, condensation of the growth regulator TORC1 coincides with its rapid inactivation, while high solubility of the stress-activated Hog1 ensures its activity across conditions. We thus uncover a fundamental organizing principle that allows tuning of cell growth to environmental fluctuations while ensuring other processes function robustly despite perturbations.

cell biology↗

bioRxiv2026

Cell wall remodeling is required for crowding homeostasis during cell growth in S. cerevisiae

The cytoplasm is a densely crowded environment that plays essential roles in intracellular functions. Its biophysical properties can be markedly altered in response to environmental cues and changes in cellular state. Recent studies have shown that excessive growth leads to cytoplasmic dilution, contributing to cellular dysfunction. However, the molecular mechanisms regulating biophysical properties during excessive growth remain poorly understood. Here, we demonstrate that cell wall remodeling is crucial to maintain cytoplasmic crowding homeostasis during cell growth. Live-cell imaging and phosphoproteomic analysis showed that Mpk1, a component of Cell Wall Integrity (CWI) pathway, accumulates in the nucleus and its activity progressively increases as cells enlarge. Mpk1 is required to restrict cell volume expansion and maintain cytoplasmic crowding by adjusting cell wall thickness and mechanical resistance. Moreover, Mpk1 is essential for the survival of enlarged cells upon cell cycle re-entry. In addition to Mpk1, we identified multiple key components of the CWI pathway that are required to maintain physiological state of enlarged cells. Together, these findings establish the CWI signaling pathway as a key regulator of cell size homeostasis and cytoplasmic biophysical properties, providing a mechanistic link between cell wall remodeling and intracellular properties.

Cell Biology↗

bioRxiv2017

The NSIGHT1 Randomized Controlled Trial: Rapid Whole Genome Sequencing for Accelerated Etiologic Diagnosis in Critically Ill Infants

ImportanceGenetic disorders, including congenital anomalies, are a leading cause of morbidity and mortality in infants, especially in neonatal and pediatric intensive care units (NICU and PICU). While genomic sequencing is useful for diagnosis of genetic diseases, results are usually reported too late to guide inpatient management.\n\nObjectiveTo test the hypothesis that rapid whole genome sequencing (rWGS) increases the proportion of infants in NICUs and PICUs receiving a genetic diagnosis within 28 days.\n\nDesignAn investigator-initiated, partially blinded, pragmatic, randomized controlled study with enrollment from October 2014 - June 2016, and follow up until December 2016.\n\nSettingA regional neonatal and pediatric intensive care unit in a tertiary referral childrens hospital.\n\nParticipantsSixty five of 129 screened families with infants aged less than four months, in neonatal and pediatric intensive care units, and with illnesses of unknown etiology, completed the study.\n\nInterventionParent and infant trio rWGS.\n\nMain Outcome and MeasureThe hypothesis and end-points were formulated a priori. The primary end-point was rate of genetic diagnosis within 28 days of enrollment or first standard test order.\n\nResultsTwenty six female proband infants, 37 male infants, and two infants of undetermined sex were randomized to receive rWGS plus standard tests (n=32, cases) or standard tests alone (n=33, controls). The study was terminated early due to loss of equipoise: 63% (21) controls received genomic sequencing as standard tests. Nevertheless, intention to treat analysis showed the rate of genetic diagnosis within 28 days to be higher in cases (31%, ten of 32) than controls (3%, one of 33; difference, 28% [95% CI, 10% to 46%]; p=0.003). Among infants enrolled in the first 25 days of life, the rate of neonatal diagnosis was higher in cases (32%, seven of 22) than controls (0%, zero of 23; difference, 32% [95% CI, 11% to 53%]; p=0.004). Age at diagnosis (median in cases 25 days, range 14-90 days vs median in controls 130 days, range 37-451) and time to diagnosis (median in cases thirteen days, range 1-84 days vs median in controls 107 days, range 21-429 days) were significantly less in cases than controls (p=0.04).\n\nCONCLUSIONSrWGS increased the proportion of infants in a regional NICU and PICU who received a timely diagnosis of a genetic disease. Additional, adequately powered studies are needed to determine whether accelerated diagnosis is associated with improved outcomes in this setting. ClinicalTrials.gov Identifier: NCT02225522.

clinical trials↗