Table 1.

Comparisons of telomere recombination pathways

Pathway	Activating Factors	Repressing Factors	Telomere structures
ALT	BLM MRE11 NBS1 RAD50	ATRX DAXX1 ASF1	heterogeneous terminal tract lengths unpaired G and C-strand at chromosome ends ECTRs C-circles, G-circles and t-circles
S. cerevisiae type I survivor	Rad51 Rad52 Rad54 Rad55 Rad57		increased Y’ elements at chromosome ends short terminal TG1–3
S. cerevisiae type II survivor	Mre11 Rad50 Rad52 Rad59 Xrs2 Sgs1 Tel1 Mec1		heterogeneous terminal tract lengths t-circles
S. pombe linear survivor	Rad22 Rad32 Rad50 Nbs1 Rap1	Taz1 Trt1 Est1 Ku70	heterogeneous terminal tract lengths
U. maydis ALT-like	Blm Mre11	Ku70 Ku80	heterogeneous terminal tract lengths unpaired C-strand at chromosome ends linear and circular ECTRs t-circles, C-circles, and G-circles