title: Forkhead containing transcription factor Albino controls tetrapyrrole-based body pigmentation in planarian.
abstract: Pigmentation processes occur from invertebrates to mammals. Owing to the complexity of the pigmentary system, in vivo animal models for pigmentation study are limited. Planarians are capable of regenerating any missing part including the dark-brown pigments, providing a promising model for pigmentation study. However, the molecular mechanism of planarian body pigmentation is poorly understood. We found in an RNA interference screen that a forkhead containing transcription factor, Albino, was required for pigmentation without affecting survival or other regeneration processes. In addition, the body color recovered after termination of Albino double stranded RNA feeding owing to the robust stem cell system. Further expression analysis revealed a spatial and temporal correlation between Albino and pigmentation process. Gene expression arrays revealed that the expression of three tetrapyrrole biosynthesis enzymes, ALAD, ALAS and PBGD, was impaired upon Albino RNA interference. RNA interference of PBGD led to a similar albinism phenotype caused by Albino RNA interference. Moreover, PBGD was specifically expressed in pigment cells and can serve as a pigment cell molecular marker. Our results revealed that Albino controls planarian body color pigmentation dominantly via regulating tetrapyrrole biogenesis. These results identified Albino as the key regulator of the tetrapyrrole-based planarian body pigmentation, suggesting a role of Albino during stem cell-pigment cell fate decision and provided new insights into porphyria pathogenesis.
authors.affiliation: Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Jiao Tong University School of Medicine & Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.affiliation: Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Jiao Tong University School of Medicine & Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai, China.
authors.forename: Xiao-Shuai
authors.initials: XS
authors.lastname: Han
authors.affiliation: Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Jiao Tong University School of Medicine & Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences , Shanghai, China.
authors.forename: Fang-Fang
authors.initials: FF
authors.lastname: Li
authors.affiliation: Department of Cardiology, Changhai Hospital , Shanghai, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Huang
authors.affiliation: Department of Cardiology, Changhai Hospital , Shanghai, China.
authors.forename: Yong-Wen
authors.initials: YW
authors.lastname: Qin
authors.affiliation: Department of Cardiology, Changhai Hospital , Shanghai, China.
authors.forename: Xian-Xian
authors.initials: XX
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Jiao Tong University School of Medicine & Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China; Department of Cardiology, Changhai Hospital, Shanghai, China.
authors.forename: Qing
authors.identifier: 0000-0001-9834-1214
authors.initials: Q
authors.lastname: Jing
keywords: FoxP; PBGD; body color; pigmentation; planarian; tetrapyrrole