New pollen-specific receptor kinases identified in tomato, maize and Arabidopsis: the tomato kinases show overlapping but distinct localization patterns on pollen tubes.
We previously characterized LePRK1 and LePRK2, pollen-specific receptor kinases from tomato (Muschietti et al., 1998). Here we identify a similar receptor kinase from maize, ZmPRK1, that is also specifically expressed late in pollen development, and a third pollen receptor kinase from tomato, LePRK3. LePRK3 is less similar to LePRK1 and LePRK2 than either is to each other. We used immunolocalization to show that all three LePRKs localize to the pollen tube wall, in partially overlapping but distinct patterns. We used RT-PCR and degenerate primers to clone homologues of the tomato kinases from other Solanaceae. We deduced features diagnostic of pollen receptor kinases and used these criteria to identify family members in the Arabidopsis database. RT-PCR confirmed pollen expression for five of these Arabidopsis candidates; two of these are clearly homologues of LePRK3. Our results reveal the existence of a distinct pollen-specific receptor kinase gene family whose members are likely to be involved in perceiving extracellular cues during pollen tube growth.
Plant Gene Expression Center, USDA/ARS-UC-Berkeley, Albany, CA 94710, USA.
Hyun Uk
HU
Kim
Robyn
R
Cotter
Sheila
S
Johnson
Mineo
M
Senda
Peter
P
Dodds
Rima
R
Kulikauska
Weihua
W
Tang
Ines
I
Ezcura
Paul
P
Herzmark
Sheila
S
McCormick
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D006031:Glycosylation; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D018551:Solanum lycopersicum / Q000201:enzymology / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics; D010944:Plants / Q000201:enzymology / Q000235:genetics*; D011058:Pollen / Q000201:enzymology* / Q000254:growth & development; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D019657:Solanaceae / Q000201:enzymology / Q000235:genetics; D003313:Zea mays / Q000201:enzymology / Q000235:genetics
D018076:DNA, Complementary; D007527:Isoenzymes; D010940:Plant Proteins; D020794:Receptor Protein-Tyrosine Kinases