RBX1-03

• Submission order: 3
• Score rank: 4
• Format: Mini-protein
• Primary state: 4F52 main-face state
• Design method: Proteina seed plus ProteinMPNN redesign
• Description: This Proteina-derived mini-protein was brought forward because it contributes a longer non-BindCraft scaffold that touches substantially more RBX1 residues than most compact helical entries in the main-face lane. The working model targets the main RBX1 surface represented by the 4F52 Glomulin-blocked reference in the 4F52 main-face state, and current structural support remains centered on that state. The strongest parts of the metric profile are 12 binder-side residues participating in the modeled interface, a contact patch that reaches 13 RBX1 residues, moderate RBX1 surface coverage of 0.269, an early but non-zero interface-confidence signal of 0.536, acceptable developability at 0.872, and a composite ranking score of 6.3857. Novelty support is acceptable: the UniRef50 30-aa sliding-window screen is clear; no strong competing interaction is flagged in the off-target screen; the main caution is that current structural evidence is still centered on one RBX1 conformation rather than a recovered cross-state contact pattern; the full project rationale and design workflow are documented at https://github.com/tuna010101/RBX1-Binder-Design-Portfolio