In the cross-compatible pollen tube, S1-RNases, HT-B, and thioredoxin h (Trxh) enter into the non-self-pollen tube. S3-SLFs (S-locus F-boxes) form Skip Cullin F-box (SCF) complexes with SSK1, Cullin1, and Rbx to degrade S1-RNase by the ubiquitin–proteasome system (UPS). Meanwhile, actin-binding proteins have normal abundance and can bind to the cytoskeleton to maintain the order of the cytoskeleton, resulting in non-self-pollen tube growth. In the self-incompatible pollen tube, S1-RNases, HT-B, and Trxh enter into the self-pollen tube. Self S1-RNase cannot be recognized and degraded by the SCF complex, thus remaining functional and forming condensates (Initiation). Further, S1-RNase together with HT-B and Trxh forms robust S-RNase condensates (SRCs) (Expansion), which further recruit actin-binding proteins (Sequestration). The sequestration of those factors by SRCs causes the cytoskeleton to be disordered due to the lack of actin-binding proteins, generating actin foci and inhibiting self-pollen tube growth. The dashed boxes at the bottom indicate the S-RNase degradation and condensation processes, respectively. Non-self- and self-pollen tubes are generally in oxidation (yellow) and reduced (blue) states, respectively^[ref1].