Biology subjects

Lane, E.

Publications and source records attributed to Lane, E..

6 recordsLinked to original sources

bioRxiv2026

Cyclin D-CDK4/6 couple proliferation to membrane and mitochondrial protein supply through a DeSI1 phospho-switch

Cyclin D-CDK4/6 complexes drive cell-cycle entry through an RB-E2F-dependent transcriptional program, but how they coordinate proliferation with the membrane and organelle protein supply required for growth is unclear. We identify DeSI1 as a cyclin D-CDK4/6 substrate whose phosphorylation at S25 converts a latent homodimer into an active monomeric deubiquitylase that recognizes hydrophobic proteins such as those bearing transmembrane domains and mitochondrial targeting sequences. Phosphorylated DeSI1 extends the lifetime of newly synthesized hydrophobic proteins that support membrane and mitochondrial capacity. Constitutive DeSI1 activation uncouples this proteostatic program from metabolic supply, creating a cytidine-nucleotide supply-demand imbalance associated with impaired CTP-dependent phospholipid homeostasis, cardiolipin depletion, and mitochondrial decompensation - defects that cytidine reverses. In mice, constitutive DeSI1 activation causes progressive cerebellar degeneration with membrane-protein accumulation, respiratory-chain loss, and phospholipid depletion. These findings define a post-translational mechanism coupling cell-cycle entry to membrane and mitochondrial capacity, and reveal the cost of uncoupling this program from its metabolic support.

cell biology↗

bioRxiv2026

Integrated Interactomics Reveals Novel Protein Associations: The FOXA1-PBX1 Complex as a Case Study

Protein-protein interactions (PPIs) are fundamental to cellular signaling networks, yet many remain undetected due to technical limitations of individual affinity purification approaches. To address this, we systematically mapped the interaction landscapes of six regulatory proteins involved in cell proliferation, immunity, and inflammation, including three transcription factors (TFs) and three kinases. We implemented an integrated proteomics workflow that combined four complementary affinity purification strategies: native immunoprecipitation, two crosslinking-assisted capture methods, and proximity labeling. Combining these approaches revealed distinct yet overlapping interaction profiles, uncovered numerous previously unreported interactors not reliably detected by individual methods, and robustly recovered known interactions while substantially extending PPI networks. Despite method-specific differences at the protein level, functional enrichment analyses showed strong convergence on coherent biological pathways. Biochemical approaches validated most of the previously unreported interactions, including putative weak and transient complexes stabilized by crosslinking. Functional assays revealed a previously unrecognized physical interaction between FOXA1 and PBX1 TFs and demonstrated their cooperative regulation of transcriptional programs and cell fitness in estrogen receptor (ER) positive breast cells. We propose that the FOXA1-PBX1 complex could represent a higher-order regulatory node integrating chromatin accessibility and ER-driven transcriptional output. HIGHLIGHTSO_LIComplementary affinity purification strategies uncover putative weak and transient protein-protein interactions C_LIO_LIFunctional pathway convergence validates biologically coherent interactome expansion C_LIO_LIBiochemical validations confirm unreported interactions C_LIO_LIFunctional validation studies identify a FOXA1-PBX1 pioneer factor complex that regulates estrogen receptor transcriptional programs C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=191 HEIGHT=200 SRC="FIGDIR/small/738938v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@193cc1borg.highwire.dtl.DTLVardef@3d068dorg.highwire.dtl.DTLVardef@791d5corg.highwire.dtl.DTLVardef@1769ce7_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

bioRxiv2025

Cholinergic Signaling Modulates Intestinal Pathophysiology in a Drosophila Model of Cystic Fibrosis

Cystic fibrosis (CF) is a monogenic genetic disease caused by mutations in the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) chloride/bicarbonate channel, which is expressed in certain epithelial cells. Current therapies focus on restoring CFTR function, but many gut-related pathologies persist, highlighting the need for complementary treatments to improve the quality of life of people with CF. In this study, we use Drosophila melanogaster as a model to investigate the gut-specific effects of Cftr loss. We demonstrate that enterocyte specific knockdown of Cftr in flies recapitulates several CF pathologies, including reduced intestinal motility, nutrient malabsorption, and decreased energy stores. Using single-nuclei RNA sequencing (snRNA-seq), we identify significant transcriptional changes in the CF model gut, including the upregulation of acetylcholine esterase (Ace, human AChE), which leads to reduced cholinergic signaling. Cholinergic signaling has been shown to affect CFTR function but this is the first time CFTR loss of function has been shown to alter cholinergic signaling. Functional assays confirm that cholinergic sensitivity is diminished in CF guts. Furthermore, restoring cholinergic signaling via Ace knockdown rescues multiple CF-associated phenotypes. Additionally, we identify the transcription factor Fork head (Fkh), the Drosophila homolog of human FOXA1/FOXA2, which is known to be a positive regulator of Cftr transcription in the intestine, as a positive regulator of Ace expression in CF guts. This study establishes the Drosophila gut as a powerful model to investigate CF pathogenesis, genetic modifiers, and identifies Ace and fkh as genetic modifiers. This work also suggests that enhancing cholinergic signaling may represent a viable therapeutic strategy for gastrointestinal manifestations of CF. Author SummaryCystic fibrosis (CF) is a genetic disease that causes complications in multiple organ systems, including the lungs and gastrointestinal tract. While recent therapies have greatly improved life span and respiratory outcomes in people with CF (pwCF), they continue to report significant gastrointestinal symptoms that impact their quality of life. Therefore, there is a need to better understand the progression of CF in the gut and identify gut specific therapeutic targets to improve patient quality of life. In this study we use Drosophila to model gut specific complications of CF. We show our model recapitulates many CF clinical presentations in the gut demonstrating our model may be clinically relevant. Furthermore, we identify acetylcholine esterase (Ace) as a gene that is increased in our CF model guts that is important for the development of CF pathologies. We additionally, perform a screen to identify a transcriptional regulator of Ace, whose genetic manipulation also regulates CF phenotypes. Our findings not only identify a potential target to alleviate GI symptoms in patients with CF, but also validate the Drosophila gut as a robust model for studying CF pathogenesis, genetic modifiers, and screening therapeutics.

genetics↗

bioRxiv2024

Stabilization of GTSE1 by cyclin D1-CDK4/6 promotes cell proliferation: relevance in cancer prognosis

In healthy cells, cyclin D1 is expressed during the G1 phase of the cell cycle, where it activates CDK4 and CDK6. Its dysregulation is a well-established oncogenic driver in numerous human cancers. The cancer-related function of cyclin D1 has been primarily studied by focusing on the phosphorylation of the retinoblastoma (RB) gene product. Here, using an integrative approach combining bioinformatic analyses and biochemical experiments, we show that GTSE1 (G-Two and S phases expressed protein 1), a protein positively regulating cell cycle progression, is a previously unrecognized substrate of cyclin D1-CDK4/6 in tumor cells overexpressing cyclin D1 during G1 and subsequent phases. The phosphorylation of GTSE1 mediated by cyclin D1-CDK4/6 inhibits GTSE1 degradation, leading to high levels of GTSE1 across all cell cycle phases. Functionally, the phosphorylation of GTSE1 promotes cellular proliferation and is associated with poor prognosis within a pan-cancer cohort. Our findings provide insights into cyclin D1s role in cell cycle control and oncogenesis beyond RB phosphorylation.

biochemistry↗

bioRxiv2024

D-type cyclins regulate DNA mismatch repair in the G1 and S phases of the cell cycle, maintaining genome stability

The large majority of oxidative DNA lesions occurring in the G1 phase of the cell cycle are repaired by base excision repair (BER) rather than mismatch repair (MMR) to avoid long resections that can lead to genomic instability and cell death. However, the molecular mechanisms dictating pathway choice between MMR and BER have remained unknown. Here, we show that, during G1, D-type cyclins are recruited to sites of oxidative DNA damage in a PCNA- and p21-dependent manner. D-type cyclins shield p21 from its two ubiquitin ligases CRL1SKP2 and CRL4CDT2 in a CDK4/6-independent manner. In turn, p21 competes through its PCNA-interacting protein degron with MMR components for their binding to PCNA. This inhibits MMR while not affecting BER. At the G1/S transition, the CRL4AMBRA1-dependent degradation of D-type cyclins renders p21 susceptible to proteolysis. These timely degradation events allow the proper binding of MMR proteins to PCNA, enabling the repair of DNA replication errors. Persistent expression of cyclin D1 during S-phase increases the mutational burden and promotes microsatellite instability. Thus, the expression of D-type cyclins inhibits MMR in G1, whereas their degradation is necessary for proper MMR function in S. One-Sentence SummaryTo maintain genome stability, D-type cyclins limit mismatch repair (MMR) in G1, whereas their degradation is necessary for proper MMR function in S phase.

cell biology↗

bioRxiv2021

Perceiving and remembering speech depend on nonlinearity in movements producing and exploring speech

Speech perception and memory for speech require active engagement. Gestural theories have emphasized mainly the effect of speakers movements on speech perception. They fail to address the effects of listener movement, focusing on communication as a boundary condition constraining movement among interlocutors. The present work attempts to break new ground by using multifractal geometry of physical movement as a common currency for supporting both sides of the speaker-listener dyads. Participants self-paced their listening to a narrative, after which they completed a test of memory querying their narrative comprehension and their ability to recognize words from the story. The multifractal evidence of nonlinear interactions across timescales predicted the fluency of speech perception. Self-pacing movements that enabled listeners to control the presentation of speech sounds constituted a rich exploratory process. The multifractal nonlinearity of this exploration supported several aspects of memory for the perceived spoken language. These findings extend the role of multifractal geometry in the speakers movements to the narrative case of speech perception. In addition to posing novel basic research questions, these findings make a compelling case for calibrating multifractal structure in text-to-speech synthesizers for better perception and memory of speech.

neuroscience↗