Table 1 Expression of the selected genes in the spiralian brains

Lineus ruber

Nemertea

Complex

Broadly expressed with the exception of ventro-median domain

this study

Ventral brain, dorso-lateral domains

this study

Scattered expression in ventral, dorso-lateral and dorso-posterior domains

this study

Dorsal brain, ventro-lateral domains

This study

Platynereis dumerilii

Annelida

Complex

Paired lateral domains

[47, 54]

Ventro-median domain

[47, 54]

No expression in the brain

[46]

anterior brain

[47]

Dimorphilus gyrociliatus

Annelida

Compact

Paired lateral domains

[48]

Ventro-median and medio-lateral domains

[48]

No expression in the brain

[48]

N/A

Capitella teleta

Annelida

Compact

Paired lateral domains

[53]

nk2.1a: paired medio-lateral domains

nk2.1b: paired medio-lateral domains

[52]

N/A

N/A

Terebratalia transversa

Brachiopoda

Larval apical organ

Paired dorso-lateral domains

[78, 79]

Ventral domain

[51, 80]

No expression in the apical organ

[45]

N/A

Novocrania anomala

Brachiopoda

Larval apical organ

Dorso-lateral domain

[79]

Ventral domain

[80]

No expression in the apical organ

[45]

N/A

Phoronopsis harmeri

Phoronida

Larval apical organ

No expression in the apical organ

[81]

No expression in the apical organ

[82]

N/A

N/A

Schmidtea mediterranea

Platyhelminthes

Compact

pax6A: broadly expressed throughout the brain

pax6B: lateral brain

[49]

Ventral brain, dorso-median domains

[50]

No expression in the brain

[83]

N/A

Epiphanes senta

Rotifera

Compact

Paired lateral domains

[45]

nk2.1a: dorso-median domain

nk2.1b: median domain

nk2.1c: ventro-median domain

[45]

Paired lateral domains

[45]

N/A