Gene Details:

Functional Descriptions:

  • Immunostaining with Lsi1 and Lsi2 antibodies revealed a similar pattern of subcellular localization of these two Si transporters in both varieties; Lsi1 and Lsi2 were localized at the distal and proximal sides, respectively, of both exodermis and endodermis of the roots.
  • Furthermore, in the rice mutants defective in the silicon efflux transporter Lsi2, arsenite transport to the xylem and accumulation in shoots and grain decreased greatly.
  • Recent studies have shown that arsenite is taken up by rice (Oryza sativa) roots through two silicon transporters, Lsi1 (the aquaporin NIP2;1) and Lsi2 (an efflux carrier).
  • The expression of two Si transporter genes (Low silicon rice 1 [Lsi1] and Lsi2) investigated using real-time reverse transcription polymerase chain reaction revealed higher expression of both genes in Nipponbare than in Kasalath.
  • Expression of Lsi2 in Xenopus oocytes did not result in influx transport activity for silicon, but preloading of the oocytes with silicon resulted in a release of silicon, indicating that Lsi2 is a silicon efflux transporter.
  • By contrast, Lsi2 mutation had little effect on arsenite efflux to the external medium.
  • Mutation in Lsi2 had a much greater impact on arsenic accumulation in shoots and grain in field-grown rice than Lsi1.
  • Here we describe a previously uncharacterized gene, low silicon rice 2 (Lsi2), which has no similarity to Lsi1.
  • There was a negative correlation between the expression level of OsLsi1 and OsLsi2 and shoot Si accumulation when the rice seedlings were exposed to different Si supply conditions.
  • A split root experiment showed that the expression of both OsLsi1 and OsLsi2 was also down-regulated in half the roots without direct Si exposure when the other half of the roots were exposed to Si.
  • The expression level of some transporter genes including OsLsi1 and OsLsi2 for Si uptake and OsNramp5 for Mn uptake was significantly decreased in the mutant compared with the wild-type rice.
  • Root silicon deposition and its resultant reduction of sodium bypass flow is modulated by OsLsi1 and OsLsi2 in rice.
  • In summary, our results reveal that Si deposition at root endodermis and its resultant reduction of Na+ bypass flow is modulated by OsLsi1 and OsLsi2 and regulated by the expression of OsLsi1 and OsLsi2, implying that root Si deposition could be an active and physiologically-regulated process in rice.
  • In this study, we investigated the roles of OsLsi1 and OsLsi2 in Si-induced reduction of bypass flow and its resultant alleviation of salt stress by using lsi1 and lsi2 mutants (defective in OsLsi1 and OsLsi2, respectively) and their wild types (WTs).
  • The polar localization of both OsLsi1 and OsLsi2 was not altered by Si supply, but their protein abundance was reduced.
  • The polar localization of OsLsi1 and OsLsi2 was not altered by inhibition of clathrin-mediated endocytosis (CME) by dominant-negative induction of dynamin-related protein1A and knockout of mu subunit of adaptor protein 2 complex, although the knockout mutants of OsAP2M gene showed dwarf phenotype.

Literature:

Gene Resources:

Sequences:

cDNA Sequence
  • >LOC_Os03g01700.1
    AGCATCAGCAGCGCATGCACTAGCAGCTTAGCTACTGCGCGCGTACCAGAGAGAGATCATCAGCTCAAGTAGCTAAGCTAGCTATAATCTGCTAGCTAGCTCGATCAGACACTTAATTACCTGCTAGGTGGTGGTCGATCGAAGAAGAAGAAGATGAGTGAGCTTGCGTCGGCGCCCAAGGTGGCGCTTGGATCGATCGCGTTCGCGGTGTTCTGGATGATGGCGGTGTTCCCGTCGGTGCCGTTCCTGCCGATCGGGCGGACGGCGGGGTCGCTGCTGAGCGCGGTGCTGATGGTGATATTCCACGTGATCAGCCCCGACGACGCGTACGCCTCCATCGACCTCCCAATCCTGGGCCTCCTCTTCGCCACCATGGTGGTGGGCAGCTACCTCCGGAACGCCGGGATGTTCAAGCACCTGGGGCGTCTGCTGGCGTGGAAGAGCCAGGGCGGGCGCGACCTCATGTGCCGCGTCTGCGTCGTCACCGCCCTCGCCAGCGCCCTCTTCACCAACGACACCTGCTGCGTCGTCCTCACCGAGTTCGTCCTCGAGCTCGCCGCCGAGCGCAACCTCCCCGCCAAGCCCTTCCTCCTCGCCCTCGCCTCCAGCGCCAACATCGGCTCCGCCGCCACCCCCATCGGCAACCCCCAGAACCTGGTCATCGCCTTCAATAGCAAGATCACCTTCCCCAAGTTCCTCATGGGAATCCTCCCGGCCATGCTCGTCGGGATGGCCGTCAACATGGTCATGCTGCTCTGCATGTACTGGAGGGAGCTGGGCGGAGGGGCCGAGCTCAGCGTCGACGGCAAGCAGATGGAGGCGGTGGAGGAAGGCAGGTCGCCGGCGTCGGCCAAGAGCACGCCGCAGCTGAACGGCAACGGCAACACGATGATGTCGCTGGAGATGTCGGAGAACATAACGACCAAGCACCCATGGTTCATGCAGTGCACGGAGGCGCGGCGGAAGCTGTTCCTCAAGAGCTTCGCGTACGTGGTGACGGTGGGGATGGTGGTGGCCTACATGGTGGGGCTCAACATGTCGTGGACGGCCATCACCACGGCGCTGGCGCTGGTGGTGGTCGACTTCCGCGACGCCGAGCCGTGCCTGGACACCGTGTCCTACTCGCTGCTCGTCTTCTTCTCCGGGATGTTCATCACCGTCAGCGGCTTCAACAAGACGGGCCTCCCGGGAGCCATCTGGGACTTCATGGCCCCCTACTCCAAGGTCAACAGCGTCGGCGGCATCTCCGTCCTCTCCGTCATCATCCTCCTCCTCTCCAACCTCGCATCAAACGTACCAACGGTGCTTCTTATGGGTGATGAGGTGGCGAAGGCGGCGGCGCTGATATCGCCGGCGGCGGTGACGACGTCGTGGCTGCTGCTGGCGTGGGTGAGCACGGTGGCGGGGAACCTGTCGCTGCTGGGGTCGGCGGCGAACCTGATAGTGTGCGAGCAGGCGAGGAGGGCGCCCAGGAACGCCTACGACCTCACCTTCTGGCAGCACATCGTCTTCGGCGTCCCATCCACCCTCATCGTCACCGCCGTCGGCATACCCCTCATCGGCAAGATCTGATCTCATCTCATCGACCCATCCAAATTAATTAATTATGAGATCGACAAACATCCAAGCTTGCTAGGCTCGTCGTCGTCGTCGTCGACCACCGTACCATATATATGCATGCATGCCACGCACGTATATATATGCTCCTCAACCTCAAGTCAATTAATTAAGAGAATGGATGAATGAATCAATGTTGTGTATGATTTCCTTTTTGTTTTTGTTTTACCCACCGTATATGTGCTGTGTGGTGTATGGCCGGCGAGCTTGAAATTGAATTGGCCTTGCTTGCATGCATGCATGGTGATCAGATCAGCTCAGCTAGCTAGCTAAATCTTGCTTAATTTTATCAAGTGTCAATCATGATGAGAAGAGAGGGAACTAGATGGAGCTAGCTAGCTAGCAACACATGCAGTGTGTGCTAAGCAGTGCACTCTGCATGCTTAAATTTGCTTGCTTAATTCAACATCGTATTACATGTATGTTGATATGTGCATGTTCCTCAAAATACATGGAAAAAAAATGTTTCTACACATCTCAATCGTATAGAGTATGTAGCATGTCTTGTTCAAACAAATATTTGTAGCCCTCTCTCTCTCTCTCTCTTTAGGTTTATTAATTAATTAGTCTGTTCAATGTCACCTCAGTTCATAGAGATGCTATACTTAATTAATTGCTCCATGTATGCAGAGTTGTACTACCTTAAAATATCAGTATGCATGCTCTTGTTGCCATTCCAAAAGAACAAA
CDS Sequence
  • >LOC_Os03g01700.1
    ATGAGTGAGCTTGCGTCGGCGCCCAAGGTGGCGCTTGGATCGATCGCGTTCGCGGTGTTCTGGATGATGGCGGTGTTCCCGTCGGTGCCGTTCCTGCCGATCGGGCGGACGGCGGGGTCGCTGCTGAGCGCGGTGCTGATGGTGATATTCCACGTGATCAGCCCCGACGACGCGTACGCCTCCATCGACCTCCCAATCCTGGGCCTCCTCTTCGCCACCATGGTGGTGGGCAGCTACCTCCGGAACGCCGGGATGTTCAAGCACCTGGGGCGTCTGCTGGCGTGGAAGAGCCAGGGCGGGCGCGACCTCATGTGCCGCGTCTGCGTCGTCACCGCCCTCGCCAGCGCCCTCTTCACCAACGACACCTGCTGCGTCGTCCTCACCGAGTTCGTCCTCGAGCTCGCCGCCGAGCGCAACCTCCCCGCCAAGCCCTTCCTCCTCGCCCTCGCCTCCAGCGCCAACATCGGCTCCGCCGCCACCCCCATCGGCAACCCCCAGAACCTGGTCATCGCCTTCAATAGCAAGATCACCTTCCCCAAGTTCCTCATGGGAATCCTCCCGGCCATGCTCGTCGGGATGGCCGTCAACATGGTCATGCTGCTCTGCATGTACTGGAGGGAGCTGGGCGGAGGGGCCGAGCTCAGCGTCGACGGCAAGCAGATGGAGGCGGTGGAGGAAGGCAGGTCGCCGGCGTCGGCCAAGAGCACGCCGCAGCTGAACGGCAACGGCAACACGATGATGTCGCTGGAGATGTCGGAGAACATAACGACCAAGCACCCATGGTTCATGCAGTGCACGGAGGCGCGGCGGAAGCTGTTCCTCAAGAGCTTCGCGTACGTGGTGACGGTGGGGATGGTGGTGGCCTACATGGTGGGGCTCAACATGTCGTGGACGGCCATCACCACGGCGCTGGCGCTGGTGGTGGTCGACTTCCGCGACGCCGAGCCGTGCCTGGACACCGTGTCCTACTCGCTGCTCGTCTTCTTCTCCGGGATGTTCATCACCGTCAGCGGCTTCAACAAGACGGGCCTCCCGGGAGCCATCTGGGACTTCATGGCCCCCTACTCCAAGGTCAACAGCGTCGGCGGCATCTCCGTCCTCTCCGTCATCATCCTCCTCCTCTCCAACCTCGCATCAAACGTACCAACGGTGCTTCTTATGGGTGATGAGGTGGCGAAGGCGGCGGCGCTGATATCGCCGGCGGCGGTGACGACGTCGTGGCTGCTGCTGGCGTGGGTGAGCACGGTGGCGGGGAACCTGTCGCTGCTGGGGTCGGCGGCGAACCTGATAGTGTGCGAGCAGGCGAGGAGGGCGCCCAGGAACGCCTACGACCTCACCTTCTGGCAGCACATCGTCTTCGGCGTCCCATCCACCCTCATCGTCACCGCCGTCGGCATACCCCTCATCGGCAAGATCTGA
Protein Sequence
  • >LOC_Os03g01700.1
    MSELASAPKVALGSIAFAVFWMMAVFPSVPFLPIGRTAGSLLSAVLMVIFHVISPDDAYASIDLPILGLLFATMVVGSYLRNAGMFKHLGRLLAWKSQGGRDLMCRVCVVTALASALFTNDTCCVVLTEFVLELAAERNLPAKPFLLALASSANIGSAATPIGNPQNLVIAFNSKITFPKFLMGILPAMLVGMAVNMVMLLCMYWRELGGGAELSVDGKQMEAVEEGRSPASAKSTPQLNGNGNTMMSLEMSENITTKHPWFMQCTEARRKLFLKSFAYVVTVGMVVAYMVGLNMSWTAITTALALVVVDFRDAEPCLDTVSYSLLVFFSGMFITVSGFNKTGLPGAIWDFMAPYSKVNSVGGISVLSVIILLLSNLASNVPTVLLMGDEVAKAAALISPAAVTTSWLLLAWVSTVAGNLSLLGSAANLIVCEQARRAPRNAYDLTFWQHIVFGVPSTLIVTAVGIPLIGKI*