In Vivo Function of the ER-Golgi Transport Protein LMAN1 in Photoreceptor Homeostasis.

LMAN1 is a type I transmembrane protein that selectively transports its cargo proteins from ER to ER-Golgi intermediate compartment (ERGIC) and Golgi. <italic>Lman1</italic> is a direct target of the transcription factor NRL in mouse retina. Therefore, we examined the in vivo function of LMAN1 in retina. Although <italic>Lman1</italic>^{<italic>-</italic><italic>/</italic><italic>-</italic>} mouse eyes did not show abnormality in histology and electroretinogram analysis at 3 months, <italic>Lman1</italic>^{<italic>-</italic><italic>/</italic><italic>-</italic>} retina at 6 months showed a decrease in cis-Golgi markers GM130 and GRASP65. We also observed abnormal level and location of Rhodopsin in these mice. Taken together, LMAN1 may play a role in photoreceptor gene transport and homeostasis. [ABSTRACT FROM AUTHOR]