Global Analysis of Intercellular Homeodomain Protein Transfer

• Published in: Cell reports (Cambridge) Vol. 28; no. 3; pp. 712 - 722.e3
• Main Authors: Lee, Eun Jung, Kim, Namsuk, Park, Jun Woo, Kang, Kyung Hwa, Kim, Woo-il, Sim, Nam Suk, Jeong, Chan-Seok, Blackshaw, Seth, Vidal, Marc, Huh, Sung-Oh, Kim, Dongsup, Lee, Jeong Ho, Kim, Jin Woo
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 16.07.2019; Elsevier
• Subjects: cell-penetrating protein; homeodomain; intercellular protein transfer; protein secretion; intercellular protein transfer; cell-penetrating protein; homeodomain; protein secretion
• ISSN: 2211-1247; 2211-1247
• DOI: 10.1016/j.celrep.2019.06.056

The homeodomain is found in hundreds of transcription factors that play roles in fate determination via cell-autonomous regulation of gene expression. However, some homeodomain-containing proteins (HPs) are thought to be secreted and penetrate neighboring cells to affect the recipient cell fate. To determine whether this is a general characteristic of HPs, we carried out a large-scale validation for intercellular transfer of HPs. Our screening reveals that intercellular transfer is a general feature of HPs, but it occurs in a cell-context-sensitive manner. We also found the secretion is not solely a function of the homeodomain, but it is supported by external motifs containing hydrophobic residues. Thus, mutations of hydrophobic residues of HPs abrogate secretion and consequently interfere with HP function in recipient cells. Collectively, our study proposes that HP transfer is an intercellular communication method that couples the functions of interacting cells. [Display omitted] •Intercellular transfer is a general feature of homeodomain proteins (HPs)•HP secretion is a cell-context-sensitive event•Hydrophobic residues outside of the homeodomain support the secretion of HP Lee et al. evaluate capabilities of homeodomain proteins (HPs) for transfer between cells. They find that intercellular transfer is a general but cell-context-sensitive property of HP. Intercellular HP transfer can be an unconventional way for the cells to communicate with neighboring cells that associate structurally and functionally.