Disease relevance of SLC7A4

• The expression of SLC7A4 can be induced in NT2 teratocarcinoma cells by treatment with retinoic acid [1].
• In addition, human glioblastoma cells stably overexpressing a fusion protein between SLC7A4 and the enhanced green fluorescent protein (EGFP) did not exhibit an increased transport activity for l-arginine [1].
• Karyotype complexity and VH gene status in B-cell chronic lymphocytic leukemia [2].

High impact information on SLC7A4

• In 4 CLL cases with unmutated VH genes, a common minimal 3.5-Mb gain of 2p16 spanning the REL and BCL11A oncogenes was identified, implicating these genes in the pathogenesis of CLL [3].
• We expressed SLC7A4 in Xenopus laevis oocytes, but could not detect any transport activity for cationic, neutral or anionic amino acids or for the polyamine putrescine [1].
• Expression of solute carrier 7A4 (SLC7A4) in the plasma membrane is not sufficient to mediate amino acid transport activity [1].
• However, also for this endogenously expressed SLC7A4, we could not detect any transport activity for l-arginine [1].
• Member 4 of human solute carrier family 7 (SLC7A4) exhibits significant sequence homology with the SLC7 subfamily of human cationic amino acid transporters (hCATs) [Sperandeo, Borsani, Incerti, Zollo, Rossi, Zuffardi, Castaldo, Taglialatela, Andria and Sebastio (1998) Genomics 49, 230-236] [1].

Biological context of SLC7A4

• The hCAT-2 gene structure is closely related to the structure of hCAT-1, suggesting that they belong to a common gene family. hCAT-4 consists of only 4 translated exons and 3 short introns [4].
• By screening an expressed sequence tag database, we identified a novel human gene, SLC7A4, encoding a solute carrier family 7 [cationic amino acid (CAA) CAT-4 transporter, y+ system] member 4 [5].
• Cationic amino acid transporter (CAT) 1, CAT 4, and 4F2hc were detected using RT-PCR in placentas throughout gestation. rBAT was not detected in term placentas [6].
• The VH mutational status correlated with high-risk cytogenetic aberrations while no such relation could be demonstrated for specific VH gene usage (V3-21 and V1-69) [2].
• Mean numbers in Ringers's solution were 90,000 at a hyperpolarizing holding potential VH = -40 mV, 50,000 at the resting potential (VH = 0 mV) and 30,000 at a depolarizing holding potential VH = 30 mV [7].

Anatomical context of SLC7A4

• Microinjection of SLC7A4 mRNA into Xenopus laevis oocytes demonstrates a significant stimulation of CAA transport [5].
• Taken together, 62 of 63 cells analyzed harbored somatically mutated VH region genes, indicating that the vast majority of both IgA- and IgM-secreting intestinal plasma cells derive from germinal center B cells [8].
• Human IgA- and IgM-secreting intestinal plasma cells carry heavily mutated VH region genes [8].
• Single IgA- or IgM-secreting plasma cells were isolated from histological sections of human jejunum and terminal ileum, and Ig heavy chain variable (VH) region genes were amplified and sequenced [8].
• The positioning of procaine among the components of human erythrocyte membranes was investigated by electron paramagnetic resonance (EPR) using several spin labelled molecules: fatty acids 5-, 12- and 16-doxyl-stearic acids (5DSA, 12DSA, 16DSA), procaine (SLP) and a quaternary ammonium salt (CAT4) [9].

Enzymatic interactions of SLC7A4

• The gene encoding a cationic amino acid transporter (SLC7A4) maps to the region deleted in the velocardiofacial syndrome [5].

Other interactions of SLC7A4

• By chromosomal in situ hybridization and YAC identification, SLC7A4 was mapped to 22q11.2, the commonly deleted region of the velocardiofacial syndrome (VCFS, Shprintzen syndrome) [5].
• Stimulus sets consisted of 92 pictures, divided in four emotional categories that ranged from neutral scenes of domestic objects (CAT1) to extremely negative scenes of mutilation or accidents (CAT4) [10].

Analytical, diagnostic and therapeutic context of SLC7A4

• B-cell chronic lymphocytic leukemia-related genomic changes were analyzed by karyotyping, fluorescence in situ hybridization, and VH gene sequencing in a prospective clinical evaluation [2].

References