The Dr-nanos gene is essential for germ cell specification in the planarian Dugesia ryukyuensis

Haruka Nakagawa, Hirotsugu Ishizu, Ayako Chinone, Kazuya Kobayashi, Midori Matsumoto

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Homologs of nanos are required for the formation and maintenance of germline stem cell (GSC) systems and for gametogenesis in many metazoans. Planarians can change their reproductive mode seasonally, alternating between asexual and sexual reproduction; they develop and maintain their somatic stem cells (SSCs) and GCSs from pluripotent stem cells known as neoblasts. We isolated a nanos homolog, Dr-nanos, from the expressed sequence tags (ESTs) of the sexualized form of Dugesia ryukyuensis. We examined the expression of Dr-nanos in asexual and sexualized planarians by in situ hybridization and analyzed its function using RNA interference (RNAi) together with a planarian sexualization assay. A nanos homolog, Dr-nanos, was identified in the planarian D. ryukyuensis. Dr-nanos expression was observed in the ovarian primordial cells of the asexual worms. This expression increased in proportion to sexualization and was localized in the early germline cells of the ovaries and testes. In X-ray-irradiated worms, the expression of Dr-nanos decreased to a large extent, indicating that Dr-nanos is expressed in some subpopulations of stem cells, especially in GSCs. During the sexualization process, worms in which Dr-nanos was knocked down by RNAi exhibited decreased numbers of oogonia in the ovaries and failed to develop testes, whereas the somatic sexual organs were not affected. We conclude that Dr-nanos is essential for the development of germ cells in the ovaries and testes and may have a function in the early stages of germ cell specification, but not in the development of somatic sexual organs.

Original languageEnglish
Pages (from-to)165-171
Number of pages7
JournalInternational Journal of Developmental Biology
Volume56
Issue number1-3
DOIs
Publication statusPublished - 2012

Fingerprint

Planarians
Essential Genes
Germ Cells
Testis
Ovary
RNA Interference
Stem Cells
Oogonia
Asexual Reproduction
Gametogenesis
Pluripotent Stem Cells
Sexual Development
Adult Stem Cells
Expressed Sequence Tags
In Situ Hybridization
Maintenance
X-Rays

Keywords

  • Germ cell specification
  • Germline stem cell
  • Nanos
  • Planarian

ASJC Scopus subject areas

  • Developmental Biology
  • Embryology

Cite this

The Dr-nanos gene is essential for germ cell specification in the planarian Dugesia ryukyuensis. / Nakagawa, Haruka; Ishizu, Hirotsugu; Chinone, Ayako; Kobayashi, Kazuya; Matsumoto, Midori.

In: International Journal of Developmental Biology, Vol. 56, No. 1-3, 2012, p. 165-171.

Research output: Contribution to journalArticle

@article{12debb285291480387ec87a327e45658,
title = "The Dr-nanos gene is essential for germ cell specification in the planarian Dugesia ryukyuensis",
abstract = "Homologs of nanos are required for the formation and maintenance of germline stem cell (GSC) systems and for gametogenesis in many metazoans. Planarians can change their reproductive mode seasonally, alternating between asexual and sexual reproduction; they develop and maintain their somatic stem cells (SSCs) and GCSs from pluripotent stem cells known as neoblasts. We isolated a nanos homolog, Dr-nanos, from the expressed sequence tags (ESTs) of the sexualized form of Dugesia ryukyuensis. We examined the expression of Dr-nanos in asexual and sexualized planarians by in situ hybridization and analyzed its function using RNA interference (RNAi) together with a planarian sexualization assay. A nanos homolog, Dr-nanos, was identified in the planarian D. ryukyuensis. Dr-nanos expression was observed in the ovarian primordial cells of the asexual worms. This expression increased in proportion to sexualization and was localized in the early germline cells of the ovaries and testes. In X-ray-irradiated worms, the expression of Dr-nanos decreased to a large extent, indicating that Dr-nanos is expressed in some subpopulations of stem cells, especially in GSCs. During the sexualization process, worms in which Dr-nanos was knocked down by RNAi exhibited decreased numbers of oogonia in the ovaries and failed to develop testes, whereas the somatic sexual organs were not affected. We conclude that Dr-nanos is essential for the development of germ cells in the ovaries and testes and may have a function in the early stages of germ cell specification, but not in the development of somatic sexual organs.",
keywords = "Germ cell specification, Germline stem cell, Nanos, Planarian",
author = "Haruka Nakagawa and Hirotsugu Ishizu and Ayako Chinone and Kazuya Kobayashi and Midori Matsumoto",
year = "2012",
doi = "10.1387/ijdb.113433hn",
language = "English",
volume = "56",
pages = "165--171",
journal = "International Journal of Developmental Biology",
issn = "0214-6282",
publisher = "University of the Basque Country Press",
number = "1-3",

}

TY - JOUR

T1 - The Dr-nanos gene is essential for germ cell specification in the planarian Dugesia ryukyuensis

AU - Nakagawa, Haruka

AU - Ishizu, Hirotsugu

AU - Chinone, Ayako

AU - Kobayashi, Kazuya

AU - Matsumoto, Midori

PY - 2012

Y1 - 2012

N2 - Homologs of nanos are required for the formation and maintenance of germline stem cell (GSC) systems and for gametogenesis in many metazoans. Planarians can change their reproductive mode seasonally, alternating between asexual and sexual reproduction; they develop and maintain their somatic stem cells (SSCs) and GCSs from pluripotent stem cells known as neoblasts. We isolated a nanos homolog, Dr-nanos, from the expressed sequence tags (ESTs) of the sexualized form of Dugesia ryukyuensis. We examined the expression of Dr-nanos in asexual and sexualized planarians by in situ hybridization and analyzed its function using RNA interference (RNAi) together with a planarian sexualization assay. A nanos homolog, Dr-nanos, was identified in the planarian D. ryukyuensis. Dr-nanos expression was observed in the ovarian primordial cells of the asexual worms. This expression increased in proportion to sexualization and was localized in the early germline cells of the ovaries and testes. In X-ray-irradiated worms, the expression of Dr-nanos decreased to a large extent, indicating that Dr-nanos is expressed in some subpopulations of stem cells, especially in GSCs. During the sexualization process, worms in which Dr-nanos was knocked down by RNAi exhibited decreased numbers of oogonia in the ovaries and failed to develop testes, whereas the somatic sexual organs were not affected. We conclude that Dr-nanos is essential for the development of germ cells in the ovaries and testes and may have a function in the early stages of germ cell specification, but not in the development of somatic sexual organs.

AB - Homologs of nanos are required for the formation and maintenance of germline stem cell (GSC) systems and for gametogenesis in many metazoans. Planarians can change their reproductive mode seasonally, alternating between asexual and sexual reproduction; they develop and maintain their somatic stem cells (SSCs) and GCSs from pluripotent stem cells known as neoblasts. We isolated a nanos homolog, Dr-nanos, from the expressed sequence tags (ESTs) of the sexualized form of Dugesia ryukyuensis. We examined the expression of Dr-nanos in asexual and sexualized planarians by in situ hybridization and analyzed its function using RNA interference (RNAi) together with a planarian sexualization assay. A nanos homolog, Dr-nanos, was identified in the planarian D. ryukyuensis. Dr-nanos expression was observed in the ovarian primordial cells of the asexual worms. This expression increased in proportion to sexualization and was localized in the early germline cells of the ovaries and testes. In X-ray-irradiated worms, the expression of Dr-nanos decreased to a large extent, indicating that Dr-nanos is expressed in some subpopulations of stem cells, especially in GSCs. During the sexualization process, worms in which Dr-nanos was knocked down by RNAi exhibited decreased numbers of oogonia in the ovaries and failed to develop testes, whereas the somatic sexual organs were not affected. We conclude that Dr-nanos is essential for the development of germ cells in the ovaries and testes and may have a function in the early stages of germ cell specification, but not in the development of somatic sexual organs.

KW - Germ cell specification

KW - Germline stem cell

KW - Nanos

KW - Planarian

UR - http://www.scopus.com/inward/record.url?scp=84859153696&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84859153696&partnerID=8YFLogxK

U2 - 10.1387/ijdb.113433hn

DO - 10.1387/ijdb.113433hn

M3 - Article

C2 - 22451004

AN - SCOPUS:84859153696

VL - 56

SP - 165

EP - 171

JO - International Journal of Developmental Biology

JF - International Journal of Developmental Biology

SN - 0214-6282

IS - 1-3

ER -