. Author manuscript; available in PMC: 2026 Sep 3.

Published in final edited form as: Nat Rev Mol Cell Biol. 2021 Sep 14;23(2):125–140. doi: 10.1038/s41580-021-00405-2

Box 2 Table.

The relative usage of different lengths of microhomology employed by the noted polymerases and ligases within NHEJ, TMEJ, and yeast a-EJ repair pathways is shown, with increasing usage of different microhomology sizes denoted by increasing darkness of blue shade. Only relative usage within pathway function is considered; these enzymes remain active with increasing size of microhomology, but larger microhomologies will not be as frequently used when shorter microhomologies are used effectively.

Species	Pathway	Context	Protein	Citation	Microhomology usage
					0	1	2	3	4	5–10	>10
Mammals	NHEJ	DSB	Pol μ	¹⁶⁶
			Pol λ	¹⁶⁶
			LIG4	¹⁶²
	TMEJ	DSB	Pol θ	^17,50,56
Worms	TMEJ	DSB	Pol θ	²⁰
Worms	TMEJ	Replication	Pol θ	^20,24,54
Flies	TMEJ	DSB	Pol θ	¹⁴
Yeast	a-EJ	DSB	POL4+POL32	^153,155
Other ligases and polymerases
By chance