穿透素是一种源自果蝇触角形成蛋白的 16 个氨基酸的肽，与TAT类似，能够穿过生物膜并被运输到细胞核。通过核磁共振光谱法研究了穿透素（P16；RQIKIWFQNRRMKWKK）与模拟生物膜的磷脂双胶束之间的相互作用。二级结构和定位研究证实了两个色氨酸残基（48W 和 56W）是细胞内化所必需的最重要的氨基酸。P16 或其缩短变体 P7（RRMKWKK）已被用于促进细胞摄取不可渗透的靶向肽，如 G7-18NATE。使用体外血脑屏障和颅内胶质母细胞瘤异种移植模型评估了脂质体或脂质体包封药物（阿霉素和厄洛替尼）的抗肿瘤功效和穿过血脑屏障的能力。将穿透素和转铁蛋白双重连接到脂质体（Tf-Pen-Lipo）显著增强了穿过血脑屏障的能力。此外，与游离药物相比，含阿霉素/厄洛替尼的 Tf-Pen-Liposomes 在肿瘤中显著积累，抑制肿瘤生长，并延长生存率。
Penetratin, a 16-mer Drosophila Antennapedia derived peptide, like TAT, crosses the biological membranes and is transported to the nucleus of the cells. The interaction between penetratin (P16; RQIKIWFQNRRMKWKK) and phospholipid bicelles mimicking biological membranes was studied by NMR spectroscopy. The secondary structure and positioning studies confirmed the two tryptophan residues (48W and 56W) as the most important amino acids required for cellular internalization . The P16 or its shortened variant P7 (RRMKWKK) has been utilized to promote cellular uptake of impermeable targeting peptides such as G7-18NATE. Antitumor efficacy and translocation across the BBB of liposomes or liposome encapsulated drugs (doxorubicin and erlotinib) were evaluated using the in vitro BBB and intracranial glioblastoma xenograft models. Dual conjugation of penetratin and transferrin to liposomes (Tf-Pen-Lipo) significantly enhanced the BBB translocation. In addition, doxorubicin/erlotinib containing Tf-Pen-Liposomes very significantly accumulated in tumors, inhibited tumor growth, and prolonged survival rate when compared to the free drugs.
单字母 H2N-RQIKIWFQNRRMKWKK-OH
多字母 H2N-Arg-Gln-Ile-Lys-Ile-Trp-Phe-Gln-Asn-Arg-Arg-Met-Lys-Trp-Lys-Lys-OH
氨基酸个数 16
分子式 C104H168N34O20S1
平均分子量(MW) 2246.73
精确分子量(Exact Mass)(MW) 2245.29
等电点(PI) -
pH=7.0时的净电荷数 7.97
GRAVY -1.73
亲水残基比例 -
消光系数 11000
溶解建议 亲水
参考文献：
Pietersz GA. et al. Vaccine. 19:1397-1405 (2001)
Christiaens B. et al. Eur J Biochem. 27(16):1187-1197 (2004).
