Disease relevance of ARFIP2

• METHODOLOGY: Age and gender of 168 patients (46: por1, 122: por2) and clinicopathological characteristics such as tumor site, lymph node metastasis, vascular invasion and serosal involvement were compared [1].
• CONCLUSIONS: There were differences in lymph node metastasis, lavage cytodiagnosis and recurrence pattern between por1 and por2 even in poorly differentiated adenocarcinoma [1].
• MIP-1beta was totally absent in all the poorly differentiated carcinomas with solid type growth pattern (por1) [2].

High impact information on ARFIP2

• A second mutant, RACV12L37 (with leucine substituted at position 37), which bound PAK but not POR1, induced JNK activation but was defective in inducing membrane ruffling and transformation [3].
• Furthermore, we observed that ARF6 interacts directly with POR1 and that this interaction was GTP dependent [4].
• A role for POR1, a Rac1-interacting protein, in ARF6-mediated cytoskeletal rearrangements [4].
• Truncated versions of POR1 inhibit the induction of membrane ruffling by an activated mutant of Rac1, V12Rac1, in quiescent rat embryonic fibroblast REF52 cells [5].
• Arfaptin 2, found in the same two-hybrid screen as arfaptin 1, is 60% identical in amino acid sequence and may or may not have an analogous function [6].

Biological context of ARFIP2

• Thus, overexpression of full-length POR1 diminished K(+)-stimulated exocytosis, and a point mutation in the effector domain of Rac1(V12) that prevents the interaction with POR1 abolished the inhibitory effect of the GTPase [7].

Anatomical context of ARFIP2

• The mitochondria are much more attacked by the lipophilic POR10 than by the hydrophilic POR1 and TPPS [8].

Physical interactions of ARFIP2

• Assays and properties of arfaptin 2 binding to Rac1 and ADP-ribosylation factors (Arfs) [9].

Other interactions of ARFIP2

• Arfaptin 2 was also ubiquitously expressed and bound to the GTP-, but not GDP-liganded form of class I ARFs, especially ARF1 [10].
• Based on our observation, we propose that arfaptin 2 is a target for GDP-Rac1 and for GTP-Arf1, and is involved in interactions between the Rac1 and Arfs signaling pathways [9].
• A synergistic effect between POR1 and ARF6 for the induction of actin polymerization was detected [4].

Analytical, diagnostic and therapeutic context of ARFIP2

• Cytotoxic and phototoxic effects were studied by means of electron microscopy and respiratory activity and compared with the effects of the hydrophilic cationic 5.10.15.20-tetrakis(1-methylpyridinium-4-yl)-21H.23H-porp hin tetraiodide (POR1) and the anionic 5.10.15.20-tetrakis(1-sulphophen-4-yl)-21H,23H-porp hin (TPPS) [8].
• Positive rate of lavage cytodiagnosis was significantly higher in por2 (38.9%), than that in por1 (9.1%) [1].

References