Molecular characterization of a novel UT-A urea transporter isoform (UT-5) in testis

被引:68
作者
Fenton, RA
Howorth, A
Cooper, GJ
Meccariello, R
Morris, ID
Smith, CP
机构
[1] Univ Manchester, Sch Biol Sci, Manchester M13 9PT, Lancs, England
[2] Univ Naples 2, Fac Med & Chirurg, I-1680168 Naples, Italy
来源
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY | 2000年 / 279卷 / 05期
关键词
urea transporter; membrane protein; testes; mouse;
D O I
10.1152/ajpcell.2000.279.5.C1425
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Urea movement across plasma membranes is modulated by specialized transporter proteins that are products of two genes, termed UT-A and UT-B. These proteins play key roles in the urinary concentrating mechanism and fluid homeostasis. We have isolated and characterized a 1.4-kb cDNA from testes encoding a new isoform (UT-A5) belonging to the UT-A transporter family. For comparison, we also isolated a 2.0-kb cDNA from mouse kidney inner medulla encoding the mouse UT-A3 homologue. The UT-A5 cDNA has a putative open reading frame encoding a 323- amino acid protein, making UT-A5 the smallest UT- A family member in terms of molecular size. Its putative topology is of particular interest, because it calls into question earlier models of UT-A transporter structure. Expression of UT-A5 cRNA in Xenopus oocytes mediates phloretin-inhibitable urea uptake and does not translocate water. The distribution of UT-A5 mRNA is restricted to the peritubular myoid cells forming the outermost layer of the seminiferous tubules within the testes and is not detected in kidney. UT-A5 mRNA levels are coordinated with the stage of testes development and increase 15 days postpartum, commensurate with the start of seminiferous tubule fluid movement.
引用
收藏
页码:C1425 / C1431
页数:7
相关论文
共 23 条
  • [21] CLONING AND REGULATION OF EXPRESSION OF THE RAT-KIDNEY UREA TRANSPORTER (RUT2)
    SMITH, CP
    LEE, WS
    MARTIAL, S
    KNEPPER, MA
    YOU, GF
    SANDS, JM
    HEDIGER, MA
    [J]. JOURNAL OF CLINICAL INVESTIGATION, 1995, 96 (03) : 1556 - 1563
  • [22] Cloning and characterization of the urea transporter UT3 - Localization in rat kidney and testis
    Tsukaguchi, H
    Shayakul, C
    Berger, UV
    Tokui, T
    Brown, D
    Hediger, MA
    [J]. JOURNAL OF CLINICAL INVESTIGATION, 1997, 99 (07) : 1506 - 1515
  • [23] UREA IN THE SEMINIFEROUS TUBULE - EVIDENCE FOR ACTIVE-TRANSPORT
    TURNER, TT
    HARTMANN, PK
    HOWARDS, SS
    [J]. BIOLOGY OF REPRODUCTION, 1979, 20 (03) : 511 - 515