High impact information on CRN1

• The coronin-like protein in yeast promotes actin polymerization and also interacts with microtubules [1].
• Likewise, in mammalian neutrophils, a coronin-like protein is also associated with the phagocytic apparatus [1].
• Further in vivo evidence that coronin regulates the Arp2/3 complex comes from the observation that crn1 and arp2 mutants display an allele-specific synthetic interaction [2].
• Microtubule binding is mediated by a region of Crn1p that contains sequences (not found in other coronins) homologous to the microtubule binding region of MAP1B [3].
• Crn1p is an abundant component of the cortical actin cytoskeleton and binds to F-actin with high affinity (Kd 6 x 10(-9) M) [3].

Biological context of CRN1

• Filament cross-linking depends on the coiled coil domain of Crn1p, suggesting a requirement for Crn1p dimerization [3].
• We isolated and characterized a cDNA encoding a coronin-like protein in A. healyi by sequence analysis and demonstrated intracellular localization of the gene product by transient transfection [4].

Other interactions of CRN1

• The inhibition occurs specifically in the absence of preformed actin filaments, suggesting that Crn1 may restrict Arp2/3 complex activity to the sides of filaments [2].
• Crn1p also binds to microtubules in vitro, and microtubule binding is enhanced by the presence of actin filaments [3].

References