Dubroff L M
Proc Natl Acad Sci U S A. 1977 Jun;74(6):2217-21. doi: 10.1073/pnas.74.6.2217.
Three classes of heterogeneous nuclear RNA (HnRNA) alpha, beta, and gamma, with different chemical and physical properties, can be identified in the early sea urchin embryo by hybridization with poly(U). The relative amounts of these classes vary as a function of embryonic development. It is demonstrated here that the adenyl-containing classes of HnRNA, alpha and beta, can be subfractionated by hybridization with poly(A)-agarose into species containing and lacking oligo(U)-enriched segments. These oligo(U) segments could not be detected in gamma HnRNA, which was previously shown to also lack adenylate segments. The relative proportions of these species undergo marked changes during development from early blastula (7 hr) to mesenchyme blastula (20 hr). I propose models to explain the possible effects of complementary sequences of adenylate and uridylate on the secondary structure of HnRNA, and speculate on the functional significance of such complexes.
通过与聚(U)杂交,可在海胆早期胚胎中鉴定出具有不同化学和物理性质的三类异质核RNA(HnRNA),即α、β和γ。这些类别的相对含量随胚胎发育而变化。本文证明,含腺苷酸的HnRNA类别α和β可通过与聚(A)-琼脂糖杂交进一步细分,分为含有和缺乏富含寡聚(U)片段的物种。在γ HnRNA中未检测到这些寡聚(U)片段,此前已表明γ HnRNA也缺乏腺苷酸片段。从早期囊胚(7小时)到间充质囊胚(20小时)的发育过程中,这些物种的相对比例发生了显著变化。我提出模型来解释腺苷酸和尿苷酸互补序列对HnRNA二级结构的可能影响,并推测此类复合物的功能意义。