Table 3. Subcellular localization patterns of polarisome components during key developmental stages in N. crassa.

	SPA-2	BUD-6	BNI-1	Colocalization‡	Unique roles
Conidium	cytoplasmic1	cytoplasmic, random cortical clusters, clusters at cell poles	cytoplasmic, random cortical clusters	BUD-6 & BNI-1 in random cortical clusters of unknown function	BUD-6: persistent clusters at cell poles
CSB	-	-	recruitment to incipient polarisation sites	-	BNI-1: recruitment during polarity establishment
Germ tube	apical cap2	apical cap, at septa	apical cap	SPA-2, BUD-6 & BNI-1: apical cap prior to Spk appearance	-
CAT	apical cap, transient ring at opening fusion pore	apical cap, transient ring at opening fusion pore, random cortical clusters	apical cap, at opening fusion pore, random cortical clusters	SPA-2, BUD-6 & BNI-1: apical cap during CAT homing and transient ring during fusion pore formation	-
Hyphal tip	at Spk and fan-shaped apical dome2	subapical cloud, excluded from Spk	in Spk core, apical cap3	SPA-2 & BNI-1: partial overlap in the Spk and potentially in the tip apex	BUD-6: subapical cloud, excluded from Spk
Branching	apical cap at emerging and growing branch2	subapical accumulation coincides with Spk assembly	cortical recruitment to incipient branch site	-	BNI-1: cortical recruitment during branch initiation
Septal plugging & regeneration of tip growth	recruitment to septal plug prior to repolarization, apical cap at repolarizing tip	permanently at septal pore, concentrates at septal plug, apical cap at repolarizing tip	recruitment to septal plug prior to repolarization, apical cap at repolarizing tip	SPA-2, BUD-6 & BNI-1: at septal pore and as apical cap at repolarizing tip	BUD-6: remains at septal pore/Woronin body
Septum formation in mature hyphae	-2	at incipient septation site, contractile ring, persistence at septal pore	at incipient septation site, contractile ring3	BUD-6 & BNI-1: at incipient septation site and part of contractile ring	BUD-6: persistence at septal pore (>4 h)
VHF	apical cap, transient ring at opening fusion pore	apical cap, transient ring at opening fusion pore	apical cap, transient ring at opening fusion pore	SPA-2, BUD-6 & BNI-1: transient during all stages of the fusion process	-
Conidiophore	-	cytokinetic ring, persistence at secondary septa, random cortical clusters	cytokinetic ring, transient at separation sites, random cortical clusters	BUD-6 & BNI-1: during cell separation	BUD-6: persists at completed cell separation sites/secondary septa
KO phenotype	diffuse Spk, irregular hyphal growth2	hyperbraching, apical branching, no Spk, aconidiate, aseptate, derepressed VHF at colony edge	hyperbraching, apical branching, no Spk, aconidiate, aseptate, derepressed VHF at colony edge	Δbud-6 & Δbni-1 phenotypically very similar	-

(-) no specific subcellular recruitment observed/no colocalization indicated/no unique role observed;

^‡Colocalization inferred from identical subcellular localization patterns; CSB = cell symmetry breaking, CAT = conidial anastomosis tube, Spk = Spitzenkörper, VHF = vegetative hyphal fusion (in the mature colony), KO = knock-out (gene deletion) mutant;

References:

¹Araujo-Palmorales, Master Thesis, CICESE, 2007;

²Araujo-Palmorales et al., 2009;

³Justa-Schuch et al., 2010.