Are there any specific ultrasound findings of nodular hyperplasia ("leave me alone" lesion) to differentiate it from follicular adenoma?
The ratio of solid to cystic content, spongiform appearance, and echogenicity is a combination of US findings that may be helpful in distinguishing an NH from an FA, and may thereby help to avoid unnecessary fine-needle aspirations for "leave me alone" lesions.
We identified a LLDLL sequence in the C-terminal juxtamembrane region of ASIC2a. Deleting or mutating the LLDLL sequence increased total expression and surface levels of ASIC2a in CHO cells. Mutating either of the two LL motifs had a similar effect. We further assessed ASIC2a localization in organotypic hippocampal slice neurons. The LL motif mutants exhibited increased dendritic trafficking and elevated targeting to dendritic spines. Consistent with an efficient trafficking, the LL motif mutants increased acid-activated current density. In addition, mutating the second LL motif increased pH sensitivity of the channel. These data identify the LL motifs as a negative regulator of ASIC2a trafficking and function, and suggest novel regulatory mechanisms in acid signaling.