Differential expression and molecular characterisation of Lmo7, Myo1e, Sash1, and Mcoln2 genes in Btk-defective B-cells.
OBJECTIVE
Bruton's tyrosine kinase is crucial for B-lymphocyte development. By the use of gene expression profiling, we have identified four expressed sequence tags among 38 potential Btk target genes, which have now been characterised.


METHODS
Bioinformatics tools including data mining of additional unpublished gene expression profiles, sequence verification of PCR products and qualitative RT-PCR were used. Stimulations targeting the B-cell receptor and the protein kinase C were used to activate whole B-cell splenocytes.


RESULTS
Target genes were characterised as Lim domain only 7 (Lmo7); Myosin1e (Myo1e); SAM and SH3 domain containing 1 (Sash1); and Mucolipin2 (Mcoln2). Expression was found in cell lines of different origin and developmental stages as well as in whole B-cell splenocytes and Transitional type 1 (T1) splenic B-cells from wild type and Btk-defective mice, respectively. By the use of semi-quantitative RT-PCR we found Sash1 not to be expressed in the investigated haematopoietic cell lines, while transcripts were found in whole splenic B-cells from both wild type and Btk-defective mice, whereas Lmo7, Myo1e, and Mcoln2 were expressed in both B-cell lines and primary B-lymphocytes. Except for Lmo7, the transcript level was similarly affected by stimulation in control and Btk-defective cells.
Lindvall
Jessica M
JM
Clinical Research Center, Department of Laboratory Medicine, Karolinska Institutet, Hälsovägen 7, SE-141 57 Huddinge, Sweden. jessica.lindvall@crc.ki.se
Blomberg
K Emelie M
KE
Wennborg
Anders
A
Smith
C I Edvard
CI
D000077329:Agammaglobulinaemia Tyrosine Kinase; D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism*; D027682:Cation Transport Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D045744:Cell Line, Tumor; D019295:Computational Biology; D020869:Gene Expression Profiling; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D060588:LIM Domain Proteins; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D051379:Mice; D024461:Myosin Type I; D009218:Myosins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D041681:NIH 3T3 Cells; D011505:Protein-Tyrosine Kinases / Q000172:deficiency* / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D050053:TRPM Cation Channels; D014157:Transcription Factors / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D050051:Transient Receptor Potential Channels; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics
D027682:Cation Transport Proteins; D018398:Homeodomain Proteins; D060588:LIM Domain Proteins; C485492:Lmo7 protein, mouse; C505823:Mcoln2 protein, mouse; D008565:Membrane Proteins; D012333:RNA, Messenger; C505822:Sash1 protein, mouse; D050053:TRPM Cation Channels; D014157:Transcription Factors; D050051:Transient Receptor Potential Channels; D025521:Tumor Suppressor Proteins; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625951:Btk protein, mouse; C505821:Myo1e protein, mouse; D024461:Myosin Type I; D009218:Myosins