APHs of Yep1 are essential for its ER-phagy function.

(A) Yep1 (1–131) or Yep1 (1–150), but not Yep1(1–113), is able to support ER-phagy. (B) Yep1 (1–150) exhibited self-interaction in a co-immunoprecipitation analysis. (C) Yep1Δ (114–150) exhibited self-interaction in a co-immunoprecipitation analysis. (D) Quantification of the septum abnormality phenotypes in rtn1Δ tts1Δ cells, rtn1Δ tts1Δ yep1Δ cells, and rtn1Δ tts1Δ yep1Δ cells expressing full-length Yep1, Yep1 (1–150), or Yep1Δ (114–150) (more than 200 cells with septa were examined for each sample). (E) Summary of the truncation and internal deletion analysis of Yep1. (F) Helical wheel representations of 2 APHs of Yep1. The helical wheels were generated using HeliQuest. Hydrophobic residues are colored in yellow, hydrophilic residues in blue (R and K), red (D and E), purple (T and S), and pink (N and Q), alanine in grey, and proline in green. The HeliQuest-calculated hydrophobic moment (μH) of the helix is shown. (G) The amphipathic nature of APHs is visualized in the AlphaFold-Multimer-predicted structure. The 2 APHs and the intervening amino acid are shown in the surface representation and are colored base on hydrophobicity. The rest of Yep1 is shown in the cartoon representation. (H) Helical wheel representation and the hydrophobic moment (μH) of residues 97–113 of Yep1. (I) Helical wheel representations and the hydrophobic moments (μH) of mutated APHs. Numerical data underlying panel D can be found in S1 Data, and raw images for panels A-C can be found in S1 Raw Images.

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