Table 1.
Summary of the chimeric constructs used in this study
| Constructs | Palmitoylation motif | Filopodia induction |
|---|---|---|
| GAP-43 FL | MLCCMRRTKQVEKN | +++ |
| Paralemmin FL | -DMKKHRCKCCSIM | ++++ |
| PSD-95 FL | MDCLCIVTTKKYRY- | - |
| PSD-93 FL | MFFACYCALRTNVKK- | - |
| GAP-43 NT (GAP1-14) | MLCCMRRTKQVEKN- | ++++ |
| PSD-95 NT (PSD1-26) | MDCLCIVTTKKYRY- | - |
| PSD-93 NT (PSD1-64) | MFFACYCALRTNVKK- | - |
| β1a (1-11) | MQCCGLVHRRRY | ++ |
| NSP (416-427) | MLTCCCLWAFKT-KKYR- | ++ |
| Paralemmin CT (Para CT) | -DMKKHRCKCCSIM | ++++ |
| GAP-43 NT (GAP1-14 C3,4S) | MLSSMRRTKQVEKN- | - |
| Paralemmin FL (Para FL C334S) | -DMKKHRSKCCSIM | ++ |
| Paralemmin FL (Para FL C336S) | -DMKKHRCKSCSIM | - |
| Paralemmin FL (Para FL C334,336S) | -DMKKHRSKSCSIM | - |
| GAP-43 To PSD-95 like | ||
| PSD-93 NT/PSD-95 | MFFACYCALRTNVKK- | - |
| GAP-43 NT/PSD-95 | MLCCMRRTKQVEKN- | +++++ |
| GAP-43 NT (InsL4)/PSD-95 | MLCLCMRRTKQVEKN- | +++ |
| GAP-43 NT (R6,7I)/PSD-95 | MLCCMIITKQVEKN- | + |
| GAP-43 NT (C3L)/PSD-95 | MLLCMRRTKQVEKN- | +++ |
| GAP-43 NT (InsL4, R6,7I)/PSD-95 | MLCLCMIITKQVEKN- | - |
| PSD-95 to GAP-43 like | ||
| PSD-95 D2L, Del L4 | MLCCIVTKKYRY- | ++ |
| PSD-95 T8R | MDCLCIVRTKKYRY- | + |
| PSD-95 CCT8R | MLCCIVRTKKYRY- | ++++ |
All constructs are fused to GFP. GAP-43 FL: full-length GAP-43. Paralemmin FL: full-length paralemmin. PSD-95 FL: full-length PSD-95. PSD-93 FL: full-length PSD-93. GAP1-14: residues 1-14 of GAP-43. PSD1-26: residues 1-26 of PSD-95. PSD1-64: residues 1-64 of PSD-93. β2a (1-11): residues 1-11 of the β2a subunit of L-type calcium channel. NSP (416-427): residues 416-427 of the viral nonstructural protein NSP. Para CT: 13 residues from the C-terminus of paralemmin. GAP1-14 C3,4S: palmitoylation-deficient motif of GAP-43. Para FL C334S: Cys 334 Ser mutant full-length paralemmin. Para FL C336S: Cys 336 Ser mutant full-length paralemmin. Para FL C334,336S: Cys 334,336 Ser mutant full-length paralemmin. The following constructs were fused to PSD-95 FL: PSD-93 NT/PSD-95: palmitoylation motif of PSD-93; GAP-43 NT/PSD-95: palmitoylation motif of GAP-43 (GAP1-14); GAP-43 NT (InsL4)/PSD-95: GAP1-14 with a Leu inserted between cys3 and cys4; GAP-43 NT (R6,7I)/PSD-95: GAP1-14 with mutations of Arg 6 and Arg 7; GAP-43 NT (C3L)/PSD-95: Cys3Leu mutant GAP1-14; GAP-43 NT (InsL4, R6,7I)/PSD-95: GAP1-14 with an insertion of Leu at position 4 and mutations of Arg 6 and Arg 7 to Ileu. PSD-95 D2L, Del L4: full-length PSD-95 with Asp 2 mutated to Leu and deletion of Leu 4. PSD-95 T8R: full-length PSD-95 with a mutation of Thr 8 to Arg. PSD-95 CCT8R: full-length PSD-95 with a mutation of Asp 2 to Leu, Thr 8 to Arg and deletion of Leu 4. Constructs were scored from “-” to “++++” according to their relative ability to induce filopodia outgrowth, where “-” means a lack of filopodia inducing properties and “++++” shows maximal filopodia inducing properties. Palmitoylated cysteines are in bold and basic residues are underlined.