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Mammalian Genome

, Volume 17, Issue 8, pp 858–877 | Cite as

The rat prolactin gene family locus: species-specific gene family expansion

  • S.M. Khorshed Alam
  • Rupasri Ain
  • Toshihiro Konno
  • Jennifer K. Ho-Chen
  • Michael J. Soares
Article

Abstract

In the rat there is a large family of paralogous genes related to prolactin (PRL). Members of the PRL family are expressed in cell- and temporal-specific patterns in the anterior pituitary, uterus, and placenta. An overriding feature of the PRL family is its association with pregnancy. In this investigation, we used information derived from the public rat genome database as a tool for identifying new members of the rat PRL family. The entire rat PRL gene family locus spans approximately 1.7 megabases (Mb) on Chromosome 17. Genes possessed either 5- or 6-exon organization patterns. We provide information on three newly identified genes orthologous to previously identified members of the mouse PRL gene family [placental lactogen-Iα (PL-Iα), PL-Iβ, and proliferin (PLF)] and a new member of the PRL family, termed PRL-like protein-P (PLP-P). Information is also presented on the existence of multiple PLP-M transcripts, which are generated by alternative splicing. Expansion of the PRL family has occurred independently in rodents versus the cow and does not exist in the human and dog. Elucidation of the rat PRL gene family locus provides tools for studying the genetics and biology of the rat PRL family and new insights into species-specific gene family expansion.

Keywords

Trophoblast Cell Junctional Zone Trophoblast Giant Cell Exon Versus Chorioallantoic Placenta 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Supplementary material

supp.pdf (31 kb)

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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • S.M. Khorshed Alam
    • 1
  • Rupasri Ain
    • 1
  • Toshihiro Konno
    • 1
  • Jennifer K. Ho-Chen
    • 1
  • Michael J. Soares
    • 1
  1. 1.Institute of Maternal-Fetal Biology and the Division of Cancer & Developmental Biology, Departments of Pathology and Laboratory Medicine and Obstetrics and GynecologyUniversity of Kansas Medical CenterKansas CityUSA

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