Bio

Viviana earned her PhD in Clinical Biochemistry from the University of Cambridge (UK) in 2024, where she focused on the role of primary cilia in metabolic sensing by the hypothalamus. She then joined the Lundberg lab as a postdoc for a project in collaboration with the Chan Zuckerberg Imaging Institute. She will focus on characterizing primary cilia in the adult brain using human induced pluripotent stem cells (hIPSC).

Stanford Advisors

Contact

  • Academic
    vm412@stanford.edu
    University - Scholar Department: Bioengineering Position: Postdoctoral Scholar

Additional Info

Links

All Publications

  • A Short Sequence Targets Transmembrane Proteins to Primary Cilia. Cells Macarelli, V., Harding, E. C., Gershlick, D. C., Merkle, F. T. 2024; 13 (13)

    Abstract

    Primary cilia are finger-like sensory organelles that extend from the bodies of most cell types and have a distinct lipid and protein composition from the plasma membrane. This partitioning is maintained by a diffusion barrier that restricts the entry of non-ciliary proteins, and allows the selective entry of proteins harboring a ciliary targeting sequence (CTS). However, CTSs are not stereotyped and previously reported sequences are insufficient to drive efficient ciliary localisation across diverse cell types. Here, we describe a short peptide sequence that efficiently targets transmembrane proteins to primary cilia in all tested cell types, including human neurons. We generate human-induced pluripotent stem cell (hiPSC) lines stably expressing a transmembrane construct bearing an extracellular HaloTag and intracellular fluorescent protein, which enables the bright, specific labeling of primary cilia in neurons and other cell types to facilitate studies of cilia in health and disease. We demonstrate the utility of this resource by developing an image analysis pipeline for the automated measurement of primary cilia to detect changes in their length associated with altered signaling or disease state.

    View details for DOI 10.3390/cells13131156

    View details for PubMedID 38995007

    View details for PubMedCentralID PMC11240719

  • GLP1R agonists activate human POMC neurons bioRxiv Mazzaferro, S., et al 2024
  • Regulation of the length of neuronal primary cilia and its potential effects on signalling. Trends in cell biology Macarelli, V., Leventea, E., Merkle, F. T. 2023; 33 (11): 979-990

    Abstract

    Primary cilia protrude from most vertebrate cell bodies and act as specialized 'signalling antennae' that can substantially lengthen or retract in minutes to hours in response to specific stimuli. Here, we review the conditions and mechanisms responsible for regulating primary cilia length (PCL) in mammalian nonsensory neurons, and propose four models of how they could affect ciliary signalling and alter cell state and suggest experiments to distinguish between them. These models include (i) the passive indicator model, where changes in PCL have no consequence; (ii) the rheostat model, in which a longer cilium enhances signalling; (iii) the local concentration model, where ciliary shortening increases the local protein concentration to facilitate signalling; and (iv) the altered composition model where changes in PCL skew signalling.

    View details for DOI 10.1016/j.tcb.2023.05.005

    View details for PubMedID 37302961

    View details for PubMedCentralID PMC7615206

  • Metformin acts directly in the brain to slow features of neurodegeneration bioRxiv Harding, E. C., et al 2023
https://orcid.org/0000-0002-5875-8290