Leu (Ile/Val/Ala/Phe)-rich repeats in the amino-terminal region of DLGR-2 and the rat LH receptor. ( A) Consecutive segments (L1–L18) within the amino terminus of DLGR-2 were aligned and small gaps (–) were introduced to show that many of the aliphatic and aromatic residues in one segment occur at a similar position in the other segments. These residues are boxed. In addition, Asn residues at positions typical for Leu-rich repeats (Kobe and Deisenhofer 1994,1995) are also marked. The shaded aliphatic residues correspond to intron–exon transitions in the receptor gene and are given at the start of the repeating segments. Most of the repeating segments, therefore, are coded for by distinct exons. Only complete segments, lying within the cluster of Cys residues bordering the Leu-rich repeats of Leu-rich repeats-containing proteins (Kobe and Deisenhofer 1994,1995), are taken into account. However, 0.8 repeat flanking L1 and 0.3 repeat flanking L18 might contribute to an additional repeat (altogether 19 Leu-rich repeats) in DLGR-2. (B) Similar alignment of the rat LH receptor. Data from Bhowmick et al. (1996).