High impact information on TREML1

• TLT-1 transcripts are abundant in bone marrow cells, but not in lymphocytes, and phosphorylated TLT-1 associates with SHP-1, suggesting that it is indeed an inhibitory receptor [1].
• Here we characterize TLT-1 (TREM-like transcript-1), a putative inhibitory receptor within the TREM cluster that contains an extracellular V-set Ig domain, a proline-rich region, and an immune receptor tyrosine-based inhibitory motif (ITIM) in its cytoplasmic tail [1].
• Triggering receptor expressed on myeloid cells like transcript-1 (TLT-1) is an abundant platelet-specific, type I transmembrane receptor [2].
• The extracellular fragment of TLT-1 consists of a single, immunoglobulin-like domain connected to the platelet cell membrane by a linker region called the stalk [2].
• In contrast to previously characterized ITIM receptors, TLT1 enhanced, rather than inhibited, FcepsilonRI-mediated calcium signaling in rat basophilic leukemia cells, a property dependent on the SHP-2 recruiting classical Y281 ITIM [3].

Anatomical context of TREML1

• We report a novel triggering receptor expressed on myeloid cells (TREM) family member, TREM-like transcript-1 (TLT1), which differs from the activating members because its cytoplasmic tail contains two ITIMs at Y245 and Y281 [3].
• Therefore, TLT1 represents a new costimulatory ITIM immunoreceptor and is the second ITIM-bearing receptor to be identified in platelets after platelet endothelial cell adhesion molecule-1 [3].

Analytical, diagnostic and therapeutic context of TREML1

• In this study, we have successfully generated a monoclonal antibody that can be applied to assays, including enzyme-linked immunosorbent assay (ELISA), Western immunoblotting, immunofluorescence, and Fluorescence-Activated Cell Sorter (Becton-Dickinson) (FACS), for the study of TLT-1 functions in physiological and pathological conditions [4].

References